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What are the two main veins in the neck, returning blood from the brain to the heart?

Cardiovascular System of the Head and Neck Home > Cardiovascular System > Cardiovascular System of the Head and Neck Cardiovascular System of the Head and Neck The cardiovascular system of the head and neck includes the vital arteries that provide oxygenated blood to the brain and organs of the head, including the mouth and eyes. It also includes the veins that return deoxygenated blood from these organs to the heart. Among these blood vessels are several unique and important structures that have evolved to help maintain the continuous flow of blood to the brain. The human brain is so powerful and metabolically active that it uses about 20% of all of the oxygen and glucose taken in by the body each day.... Move up/down/left/right: Click compass arrows Rotate image: Click and drag in any direction, anywhere in the frame Identify objects: Click on them in the image 2D Interactive 3D Rotate & Zoom Change Anatomical System Change View Angle Full Cardiovascular System of the Head and Neck Description [Continued from above] . . . Any interruption in the blood flow to the brain very quickly results in the decline of mental function, loss of consciousness, and eventually death if not corrected. Oxygenated blood enters the neck from the trunk through four major arteries: the left and right vertebral arteries and the left and right common carotid arteries. The vertebral arteries travel through the transverse foramina of the cervical vertebrae before entering the skull at the foramen magnum and joining at the base of the brain to form the basilar artery. From there the basilar artery provides blood to the posterior structures of the brain, including the brain stem, cerebellum, and cerebrum. The left and right carotid arteries each divide in the neck to form the left and right internal carotid as well as the left and right external carotid arteries. The internal carotid arteries pass into the skull inferior to the brain through the left and right carotid foramina. At the base of the brain, the internal carotid arteries branch off into the left and right anterior cerebral arteries and the left and right middle cerebral arteries that supply blood to the middle and anterior regions of the brain. At the base of the brain several communicating arteries form anastomoses, or passages, between the left and right posterior cerebral, left and right internal carotid, and left and right anterior cerebral arteries. These arteries collectively form a ring of blood vessels known as the Circle of Willis. The Circle of Willis provides insurance that the brain will continue to receive blood flow in the event that one of its major arteries is blocked by allowing blood flow between all of the major arteries to all of the regions of the brain. In the neck and head exterior to the skull, the external carotid artery provides blood flow to the skin, muscles, and organs. Several major arteries - including the facial, superficial temporal, and occipital arteries - branch off from the external carotid to provide blood to the many superficial structures of the head. Three pairs of major veins return deoxygenated blood from the tissues of the head and neck to the heart. The left and right vertebral veins descend through the transverse foramina of the cervical vertebrae to drain blood from the spinal cord, cervical vertebrae, and muscles of the neck. In the head, superficial structures on the exterior of the skull are drained by the pair of external jugular veins, which descend through the neck lateral to the vertebral veins. Most importantly, the brain is drained by a group of large cavities in the dura mater layer of the meninges known as dural venous sinuses. Blood collected in these sinuses drains into the largest veins in the head and neck - the left and right internal jugular veins. The internal jugular veins collect blood from the brain as well as the superficial structures of the head and neck before descending through the neck towards the heart. Prepared by Tim Taylor, Anatomy and Physiology Instructor

What is the term fro a series of uncontrollable intakes of air caused by sudden spasms of the diaphragm?

Round One Jeopardy Template The name of Dr. Sieuss's egg-hatching elephant 100 Well-known Tasmanian-born leading lady who launched her entertainment career under the name of Queenie O'Brien. 100 What is the kitchen? Room in the average American home that is the scene of the greatest number of arguments. 100 The distance between bases on a little league baseball field. 100 The part of the brain that regulates physiological stability. 200 Clark Kent's high school sweetheart 200 Yves Montand was born in this country. 200 What is Truth or Consequences? Current name of the town that was formerly Hot Springs, New Mexico, that was re-named in 1960 by its citizens in honor of a popular radio show. 200 First sport in which women were invited to compete at the Olympics. 200 What is Les Miserables, by Victor Hugo, with 823 words Novel containing the longest sentence in literature 300 What are George and Michael? Brummel was George Geste was Michael The real names of Beau Brummel and Beau Geste. 300 What are Patience and Fortitude? (Names were given by Mayor Fiorello LaGuardia.) Names of the two landmark stone lions sitting in front of the New York Public Libaray at Fifth Avenue and 42nd Street in New York City. 300 What is bicycle moto x (cross)? In cross-country bike racing, what the initials BMX stand for. 300 What are hiccups? DOUBLE JEOPARDY!!! Term for a series of uncontrollable intakes of air caused by sudden spasms of the diaphragm. 400 What is The Little Engine That Could? Famous book that begins: "Chug, chug, chug. Puff, puff, puff." 400 Who is Peter Lorre? Famous actor who prepared for a career in psychiatry - studying and working with pioneer psychoanalysts Sigmund Freud and Alfred Adler - before he turned to performing. 400 What are six months? Time - in months - the average American motorist spends during his lifetime waiting for red lights to turn green. 400 Who is Jackie Robinson? (He later gained national fame playing professional baseball.) In 1939, the famous American athlete who starred on UCLA's undefeated football team and was the top scorer in the Pacific Coast Conference for basketball. 400 What is the retina?

Which part of the eye contains about 137 million light-sensitive cells in one square inch?

Eye | Creation Facts Creation Facts Evidence From Anatomy September 13th, 2009 The eye is an incredibly complex organ that moves 100,000 times in an average day. Numerous muscles and tear ducts are in place to keep the eye constantly moist, protected, and functional. Our eyes process 1.5 million bits of information simultaneously and provide 80% of the sensory stimulation sent to the brain. They receive light images traveling at 186,000 miles per second through the iris, which opens or closes to let in just the right amount of light. These images travel through a lens, made of transparent cells, which focuses them on the retina at the back of the eyeball. The retina covers less than one square inch of surface, yet this square inch contains approximately 137 million light-sensitive receptor  cells. Approximately 130 million are rod cells (designed specifically to see in black and white), and 7 million are cone cells (allowing color vision). Finally, the image is sent at a rate of 300 miles per hour to the brain for processing. How could all of this have come about by some step-by-step, random-chance evolutionary process? Mankind has designed and patterned the camera after the eye. It is only reasonable to acknowledge that the eye, which is an infinitely more complex instrument, was also designed by intelligence.

What is the more common name for the tympanic membrane?

What is the more common name for the tympanic membrane ? - Euask.com What is the more common name for the tympanic membrane ? 5 Created by expert102, 459 days ago, 352 views What is the more common name for the tympanic membrane ? √ Best Answer

What is the name for a red blood cell?

What is a Red Blood Cell? (with pictures) What is a Red Blood Cell? Originally Written By: Michael Anissimov Revised By: Jillian O Keeffe Edited By: Bronwyn Harris Last Modified Date: 08 December 2016 Copyright Protected: Top 10 facts about the world A red blood cell, or erythrocyte , is the most common type of cell in blood. It carries oxygen throughout the circulatory system, from the lungs to the rest of the body, and brings carbon dioxide waste back the other way. All of the body's tissues are dependent upon oxygen from these cells — if the flow is cut off, the tissue dies. There are several medical conditions associated with red blood cells specifically, including sickle-cell anemia, thalassemia, and spherocytosis, but changes in the amount of these cells can also be a sign of other disorders. Characteristics Red blood cells have a diameter of about 6 to 8 micrometers (millionths of a meter), which is similar in size to most cells in the body. They are round and red, with a depression in the center. Adult humans have 20 to 30 trillion of these cells in their bodies, with men having more on average than women, and each one lives for about 120 days before being broken down. They are very flexible, which is important for their functioning, since they often have to squeeze through small openings. Ad Function The main purpose of red blood cells is to transport oxygen and carbon dioxide through the circulatory system. The reason they can do this is that they contain an iron-containing protein called hemoglobin, which binds to oxygen. When the oxygen and the hemoglobin combine, they cause the cells to become bright red. This is why blood looks red when it goes outside of the body as well — when exposed to the open through a cut, the cells become exposed to a lot of atmospheric oxygen. Once all the oxygen connected to the cells is used up, then they collect carbon dioxide and other waste gases from the body and bring it back to the lungs, where they swap it for oxygen and start the cycle again. Related Disorders There are a variety of medical disorders associated with red blood cells, with one of the most common being sickle-cell disease. This is a genetic disorder that causes the cells to become stiff and sickle-shaped. This makes them unable to move properly throughout the circulatory system, and can lead to a variety of problems, including strokes, blindness, and chronic pain. Spherocytosis is another genetic condition that changes the shape of cells and makes them brittle, but unlike sickle-cell disease, it makes them spherical. Several other conditions cause red blood cell abnormalities by disrupting the proper production of hemoglobin. This includes thalassemia, a genetic disorder that causes abnormal hemoglobin molecules, and pernicious anemia, in which the body doesn't absorb enough B12, which is needed for making hemoglobin. Additionally, conditions like G6PD deficiency, hemolytic disease of the fetus and newborn, and aplastic anemia can cause problems with the creation and life of red blood cells. Besides conditions that affect the cells themselves, having an increase or decrease in the number of red blood cells in the body can be a symptom of several conditions. A high red blood cell count, also called polycythemia, can be caused by poor circulation to the kidneys, genetic heart problems, Chronic Obstructive Pulmonary Disease ( COPD ), and pulmonary fibrosis . Some people are also born with genetic variants that cause them to have higher than normal red blood cell counts. A lower than normal count can be a sign of poor nutrition, problems with bone marrow, and leukemia , among other things. Ad

What is the scientific name for the windpipe?

Windpipe | Define Windpipe at Dictionary.com windpipe the trachea of an air-breathing vertebrate. Origin of windpipe 1520-30; wind 1 + pipe 1 Dictionary.com Unabridged Examples from the Web for windpipe Expand Contemporary Examples After using her hands to clear her windpipe, she freed her eyes from the embers that were blinding her vision. Mailer's Final Gift Lawrence Schiller February 4, 2009 Historical Examples My brother felt that it must be the windpipe, because when you kicked someone there he lost his breath. The soreness in the throat may extend down the windpipe, and membranes may form there. Diphtheria Public Health Service British Dictionary definitions for windpipe Expand a nontechnical name for trachea (sense 1) related adjective tracheal Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Word Origin and History for windpipe Expand "trachea," 1520s, from wind (n.1) in the "breath" sense + pipe (n.1). Online Etymology Dictionary, © 2010 Douglas Harper

Where do the Graafian follicles develop?

Graafian follicle | definition of graafian follicle by Medical dictionary Graafian follicle | definition of graafian follicle by Medical dictionary http://medical-dictionary.thefreedictionary.com/graafian+follicle Related to graafian follicle: ovarian follicle , ovulation , corpus luteum graafian follicle  [graf´e-an] a small sac, embedded in the ovary , that encloses an ovum . At puberty each ovary has a large number of immature follicles ( primordial follicles ), each of which contains an undeveloped egg cell. About every 28 days between puberty and the onset of menopause, one of the follicles develops to maturity, or ripens, into a graafian follicle (or vesicular ovarian follicle ). As it ripens, it increases in size. The ovum within becomes larger, the follicular wall becomes thicker, and fluid collects in the follicle and surrounds the ovum. The follicle also secretes estradiol, the hormone that prepares the endometrium to receive a fertilized egg. As the follicle matures, it moves to the surface of the ovary and forms a projection. When fully mature, the graafian follicle breaks open and releases the ovum, which passes into the fallopian tubes . This release of the ovum is called ovulation ; it occurs midway in the menstrual cycle, generally about 14 days after the commencement of the menstrual flow. The released ovum travels down the tube to the uterus, a process that takes about 3 days. Meanwhile, the empty graafian follicle in the ovary becomes filled with cells containing a yellow substance, the corpus luteum . The corpus luteum secretes progesterone , a hormone that causes further change in the endometrium, allowing it to provide a good milieu in which a zygote (fertilized ovum) can grow through the stages of gestation to become a fetus . ve·sic·u·lar o·var·i·an fol·li·cle [TA] a follicle in which the primary oocyte attains its full size and is surrounded by an extracellular glycoprotein layer (zona pellucida) that separates it from a peripheral layer of follicular cells permeated by one or more fluid-filled antra; the primary oocyte occupies the cumulus oophorus; the theca of the follicle develops into internal and external layers. Any of the fluid-filled vesicles in the mammalian ovary containing a maturing ovum. graafian follicle [grä′fē·ən, -grā′-] Etymology: Reijnier de Graaf, Dutch physician, 1641-1673; L, folliculus, small bag a mature ovarian vesicle, measuring about 10 to 12 mm in diameter, that ruptures during ovulation to release the ovum. Many primary ovarian follicles, each containing an immature ovum about 35 μm in diameter, are embedded near the surface of the ovary, just below the tunica albuginea. Under the influence of the follicle-stimulating hormone from the adenohypophysis, one ovarian follicle ripens into a graafian follicle during the proliferative phase of each menstrual cycle. The cells that form the graafian follicle are arranged in a layer three to four cells thick around a relatively large volume of follicular fluid. Within the follicle the ovum grows to about 100 μm in diameter, ruptures, and is swept into the fimbriated opening of the uterine tube. The cavity of the follicle collapses when the ovum is released, and the remaining follicular cells greatly enlarge to become the corpus luteum. If the ovum is fertilized, the corpus luteum grows and becomes the corpus luteum of pregnancy, which degenerates by the end of 9 months and has a diameter of about 30 mm. As the ovarian follicle ripens into the graafian follicle, it produces estrogen, which stimulates the proliferation of the endometrium and the enlargement of the uterine glands. The growing corpus luteum produces progesterone, which triggers endometrial gland secretion and prepares the uterus to receive the fertilized ovum. If the ovum is not fertilized, the graafian follicle forms the corpus luteum of menstruation, which degenerates before the next menstrual cycle, leaving the small scarred corpus albicans. ve·sic·u·lar o·var·i·an fol·li·cle (vĕ-sik'yū-lăr ō-var'ē-ăn fol'i-kĕl) [TA] A follicle in which the oocyte attains its f

Where would you find the pisiform bone?

Pisiform (bone) - RightDiagnosis.com Pisiform (bone) Pisiform (bone): a small wrist bone that articulates only with the triquetral. Source: WordNet 2.1 Pisiform (bone): A pea-shaped carpal bone that actually sits in the tendon of the flexor carpi ulnaris muscle. Source: MeSH 2007 Terms associated with Pisiform (bone): Terms Similar to Pisiform (bone): Source - WordNet 2.1 Hierarchical classifications of Pisiform (bone) The following list attempts to classify Pisiform (bone) into categories where each line is subset of the next. WordNet 2.1 Search to find out more about Pisiform (bone):    Search Specialists by State and City   By using this site you agree to our Terms of Use . Information provided on this site is for informational purposes only; it is not intended as a substitute for advice from your own medical team. The information on this site is not to be used for diagnosing or treating any health concerns you may have - please contact your physician or health care professional for all your medical needs. Please see our Terms of Use .

What is the scientific name for the kneecap?

What is the scientific name for the knee cap? - YouTube What is the scientific name for the knee cap? Want to watch this again later? Sign in to add this video to a playlist. Need to report the video? Sign in to report inappropriate content. The interactive transcript could not be loaded. Loading... Rating is available when the video has been rented. This feature is not available right now. Please try again later. Published on Aug 1, 2013 This improves the knowledge of the children indirectly as they never know that they are learning. - Category

What is protected by the cranium?

Neuroscience For Kids - The Skull you are here: home > explore > the skull Neuroscience For Kids the skull Your 3 pound (1.4 kg) brain needs a home...your skull! Your brain is protected by several bones. There are eight bones that surround your brain: one frontal bone; two parietal bones, two temporal bones, one occipital bone, one sphenoid bone and one ethmoid bone. These eight bones make up the cranium. Another 14 bones in the face make up the entire skull. There are also three small bones in each ear . Also protecting your brain are three layers of tissue called the meninges . A few of the bones have been colored in the diagram below. There is a large opening, called the foramen magnum, located in the back of the occipital bone. This is where the medulla ends and projects out of the skull. Smaller holes in the skull, called foramina, allow nerves and blood vessels to enter and leave the cranium. The picture on the left shows the base of the skull. The places in the skull where the bones come together are called sutures. These sutures are flexible in young children, but become fixed as they age. Copyright © 1996-2011, Eric H. Chudler, All Rights Reserved.

What is the name of the large muscle just beneath the lungs?

Your Lungs & Respiratory System Your Lungs & Respiratory System What's something that you do all day, every day, no matter where you are or who you're with? (a) think about what's for lunch tomorrow (b) put your finger in your nose (c) hum your favorite song (d) breathe It's possible that some kids could say (a) or (c) or that others might even say — yikes! — (b). But every single person in the world has to say (d). Breathing air is necessary for keeping humans (and many animals) alive. And the two parts that are large and in charge when it comes to breathing? If you guessed your lungs, you're right! Your lungs make up one of the largest organs in your body, and they work with your respiratory system to allow you to take in fresh air, get rid of stale air, and even talk. Let's take a tour of the lungs! Locate Those Lungs Your lungs are in your chest, and they are so large that they take up most of the space in there. You have two lungs, but they aren't the same size the way your eyes or nostrils are. Instead, the lung on the left side of your body is a bit smaller than the lung on the right. This extra space on the left leaves room for your heart. Your lungs are protected by your rib cage, which is made up of 12 sets of ribs. These ribs are connected to your spine in your back and go around your lungs to keep them safe. Beneath the lungs is the diaphragm (say: DY-uh-fram), a dome-shaped muscle that works with your lungs to allow you to inhale (breathe in) and exhale (breathe out) air. You can't see your lungs, but it's easy to feel them in action: Put your hands on your chest and breathe in very deeply. You will feel your chest getting slightly bigger. Now breathe out the air, and feel your chest return to its regular size. You've just felt the power of your lungs! continue A Look Inside the Lungs From the outside, lungs are pink and a bit squishy, like a sponge. But the inside contains the real lowdown on the lungs! At the bottom of the trachea (say: TRAY-kee-uh), or windpipe, there are two large tubes. These tubes are called the main stem bronchi (say: BRONG-kye), and one heads left into the left lung, while the other heads right into the right lung. Each main stem bronchus (say: BRONG-kuss) — the name for just one of the bronchi — then branches off into tubes, or bronchi, that get smaller and even smaller still, like branches on a big tree. The tiniest tubes are called bronchioles (say: BRONG-kee-oles), and there are about 30,000 of them in each lung. Each bronchiole is about the same thickness as a hair. At the end of each bronchiole is a special area that leads into clumps of teeny tiny air sacs called alveoli (say: al-VEE-oh-lie). There are about 600 million alveoli in your lungs and if you stretched them out, they would cover an entire tennis court. Now that's a load of alveoli! Each alveolus (say: al-VEE-oh-luss) — what we call just one of the alveoli — has a mesh-like covering of very small blood vessels called capillaries (say: CAP-ill-er-ees). These capillaries are so tiny that the cells in your blood need to line up single file just to march through them. All About Inhaling When you're walking your dog, cleaning your room, or spiking a volleyball, you probably don't think about inhaling (breathing in) — you've got other things on your mind! But every time you inhale air, dozens of body parts work together to help get that air in there without you ever thinking about it. As you breathe in, your diaphragm contracts and flattens out. This allows it to move down, so your lungs have more room to grow larger as they fill up with air. "Move over, diaphragm, I'm filling up!" is what your lungs would say. And the diaphragm isn't the only part that gives your lungs the room they need. Your rib muscles also lift the ribs up and outward to give the lungs more space. At the same time, you inhale air through your mouth and nose, and the air heads down your trachea, or windpipe. On the way down the windpipe, tiny hairs called cilia (say: SILL-ee-uh) move gently to keep mucus and dirt out of the lungs. The air then goes thro

Where in the body is the thyroid?

The Thyroid (Human Anatomy): Picture, Function, Definition, Location in the Body, and More Next The thyroid is a butterfly-shaped gland that sits low on the front of the neck. Your thyroid lies below your Adam’s apple, along the front of the windpipe. The thyroid has two side lobes, connected by a bridge (isthmus) in the middle. When the thyroid is its normal size, you can’t feel it. Brownish-red in color, the thyroid is rich with blood vessels. Nerves important for voice quality also pass through the thyroid. The thyroid secretes several hormones, collectively called thyroid hormones. The main hormone is thyroxine, also called T4. Thyroid hormones act throughout the body, influencing metabolism, growth and development, and body temperature. During infancy and childhood, adequate thyroid hormone is crucial for brain development. Thyroid Conditions Goiter : A general term for thyroid swelling. Goiters can be harmless, or can represent iodine deficiency or a condition associated with thyroid inflammation called Hashimoto’s thyroiditis. Thyroiditis : Inflammation of the thyroid, usually from a viral infection or autoimmune condition. Thyroiditis can be painful, or have no symptoms at all. Hyperthyroidism : Excessive thyroid hormone production. Hyperthyroidism is most often caused by Graves disease or an overactive thyroid nodule. Hypothyroidism : Low production of thyroid hormone. Thyroid damage caused by autoimmune disease is the most common cause of hypothyroidism . Graves disease : An autoimmune condition in which the thyroid is overstimulated, causing hyperthyroidism. Thyroid cancer : An uncommon form of cancer, thyroid cancer is usually curable. Surgery, radiation, and hormone treatments may be used to treat thyroid cancer. Thyroid nodule : A small abnormal mass or lump in the thyroid gland. Thyroid nodules are extremely common. Few are cancerous. They may secrete excess hormones, causing hyperthyroidism, or cause no problems.  Thyroid storm : A rare form of hyperthyroidism in which extremely high thyroid hormone levels cause severe illness. Continued Thyroid Tests Anti-TPO antibodies : In autoimmune thyroid disease, proteins mistakenly attack the thyroid peroxidase enzyme, which is used by the thyroid to make thyroid hormones. Thyroid ultrasound: A probe is placed on the skin of the neck, and reflected sound waves can detect abnormal areas of thyroid tissue. Thyroid scan : A small amount of radioactive iodine is given by mouth to get images of the thyroid gland. Radioactive iodine is concentrated within the thyroid gland.  Thyroid biopsy : A small amount of thyroid tissue is removed, usually to look for thyroid cancer. Thyroid biopsy is typically done with a needle.  Thyroid stimulating hormone (TSH): Secreted by the brain, TSH regulates thyroid hormone release. A blood test with high TSH indicates low levels of thyroid hormone (hypothyroidism), and low TSH suggests hyperthyroidism. T3 and T4 (thyroxine) : The primary forms of thyroid hormone, checked with a blood test.  Thyroglobulins : A substance secreted by the thyroid that can be used as a marker of thyroid cancer. It is often measured during follow-up in patients with thyroid cancer. High levels indicate recurrence of the cancer.  Other imaging tests: If thyroid cancer has spread (metastasized), tests such as CT scans , MRI scans , or PET scans can help identify the extent of spread.  Thyroid Treatments Thyroid surgery (thyroidectomy): A surgeon removes all or part of the thyroid in an operation. Thyroidectomy is performed for thyroid cancer, goiter,  or hyperthyroidism.  Antithyroid medications : Drugs can slow down the overproduction of thyroid hormone in hyperthyroidism. Two common antithyroid medicines are methimazole and propylthiouracil.  Radioactive iodine : Iodine with radioactivity that can be used in low doses to test the thyroid gland or destroy an overactive gland. Large doses can be used to destroy cancerous tissue. External radiation : A beam of radiation is directed at the thyroid, on multiple appointments. The high-energy rays help kill thyroid c

Which organ in the body stores excess sugar as glycogen?

The Liver & Blood Sugar :: Diabetes Education Online Diabetes Education Online « Controlling Blood Sugar During a meal, your liver stores sugar for later. When you’re not eating, the liver supplies sugar by turning glycogen into glucose in a process called glycogenolysis. The liver both stores and produces sugar… The liver acts as the body’s glucose (or fuel) reservoir, and helps to keep your circulating blood sugar levels and other body fuels steady and constant. The liver both stores and manufactures glucose depending upon the body’s need. The need to store or release glucose is primarily signaled by the hormones insulin and glucagon . During a meal, your liver will store sugar, or glucose, as glycogen for a later time when your body needs it. The high levels of insulin and suppressed levels of glucagon during a meal promote the storage of glucose as glycogen. The liver makes sugar when you need it…. When you’re not eating – especially overnight or between meals, the body has to make its own sugar. The liver supplies sugar or glucose by turning glycogen into glucose in a process called glycogenolysis. The liver also can manufacture necessary sugar or glucose by harvesting amino acids, waste products and fat byproducts. This process is called gluconeogenesis. The liver also makes another fuel, ketones, when sugar is in short supply…. When your body’s glycogen storage is running low, the body starts to conserve the sugar supplies for the organs that always require sugar. These include: the brain, red blood cells and parts of the kidney. To supplement the limited sugar supply, the liver makes alternative fuels called ketones from fats. This process is called ketogenesis. The hormone signal for ketogenesis to begin is a low level of insulin. Ketones are burned as fuel by muscle and other body organs. And the sugar is saved for the organs that need it. The terms “gluconeogenesis, glycogenolysis and ketogenesis” may seem like complicated concepts or words on a biology test. Take a moment to review the definitions and illustrations above. When you have diabetes, these processes can be thrown off balance, and if you fully understand what is happening, you can take steps to fix the problem. Gluconeogenesis? Glycogenolysis? Ketogenesis? What are they? You need to know. Self-assessment Quiz Self assessment quizzes are available for topics covered in this website. To find out how much you have learned about  Facts about Diabetes, take our self assessment quiz when you have completed this section.  The quiz is multiple choice. Please choose the single best answer to each question. At the end of the quiz, your score will display. If your score is over 70% correct, you are doing very well. If your score is less than 70%, you can return to this section and review the information.

What name is given to the small bones which form the spinal column?

Bones of the Spinal Column Home  »  Spine Articles  »  Spinal Column Articles  »  Bones of the Spinal Column Bones of the spinal column  Sections The spinal column is made up of small bones called vertebrae. Offering support and structure to the human body, these bones are some of the most complex bones in the human body. Each vertebra has a specific function, working together to protect the spinal cord. Segments of the spine The spinal column is composed of a number of different segments, including the cervical (neck), thoracic (middle back) and lumbar (lower back) segments. The sacrum and coccyx are bones that are found at the base of the spine. Cervical — The cervical region usually consists of seven vertebrae (C1–7), which are the smallest bones of the spinal column. The atlas (C1) directly supports the head, while the axis (C2) provides the head with pivoting motion. The remaining bones (C3–7) allow the head to move from side to side, backward and forward. Thoracic — In most cases, twelve vertebrae (T1–12) form the thoracic region, which is generally considered the sturdiest area of the spine. This region serves to protect the organs located in the chest, so spinal mobility is limited more in the thoracic region than in the cervical and lumbar regions. Thoracic vertebrae are further supported by the attached rib cage. Lumbar — The final segment in the spine is the lumbar area. This segment usually consists of five (sometimes six) individual vertebrae (L1–5). These bones are the largest in the spinal column because they must bear the weight of the body. Sacrum — This triangular bone sits between the pelvic bones and serves to protect the pelvic organs. Consisting of five fused vertebrae (S1–5), the sacrum attaches to the L5 vertebra above and the coccyx below. Coccyx — A vestigial remnant of a tail, the coccyx is commonly known as the “tailbone.” Many essential ligaments and muscles attach to this bone. The bones of the spinal column, as well as the spinal cord, nerve roots, muscles, tendons and ligaments, can be afflicted by trauma (accidents or injuries) as well as degenerative spine conditions. When this happens, it can lead to long-term chronic pain and limited mobility. Treatment for painful spine conditions At Laser Spine Institute, we understand the importance of a healthy spine. If you are experiencing chronic neck or back pain that is affecting your quality of life, consider treatment at our outpatient surgery center. Our surgeons specialize exclusively in treating neck and back pain with minimally invasive, outpatient spine surgery . These procedures are a safer and effective alternative to traditional open neck and back surgery, offering you a number of benefits. Having helped more than 60,000 patients since 2005, our surgeons are available in cities across the country. Learn more about our advanced techniques For more information about the benefits of minimally invasive spine surgery, please call a member of our Care Team today . With a 96 patient satisfaction rate, our goal is to always provide you with the ultimate in care and comfort, so that you can return to your normal daily activities. Want to chat?

Where in the body are the cerebellum, the medulla and the hypothalamus?

Brain – Human Brain Diagrams and Detailed Information Brain Cortices Full Brain Description [Continued from above] . . . in the study of the body; doctors, psychologists, and scientists are continually endeavoring to learn exactly how the many structures of the brain work together intricately to create our powerful human mind. Anatomy of the Brain There are different ways of dividing the brain anatomically into regions. Let’s use a common method and divide the brain into three main regions based on embryonic development: the forebrain, midbrain and hindbrain. Under these divisions: The forebrain (or prosencephalon) is made up of our incredible cerebrum, thalamus, hypothalamus and pineal gland among other features. Neuroanatomists call the cerebral area the telencephalon and use the term diencephalon (or interbrain) to refer to the area where our thalamus, hypothalamus and pineal gland reside. The midbrain (or mesencephalon), located near the very center of the brain between the interbrain and the hindbrain, is composed of a portion of the brainstem. The hindbrain (or rhombencephalon) consists of the remaining brainstem as well as our cerebellum and pons. Neuroanatomists have a word to describe the brainstem sub-region of our hindbrain, calling it the myelencephalon, while they use the word metencephalon in reference to our cerebellum and pons collectively. Before exploring these different regions of the brain, first let’s define the important types of cells and tissues that are the building blocks of them all. Histology Brain cells can be broken into two groups: neurons and neuroglia. Neurons, or nerve cells, are the cells that perform all of the communication and processing within the brain. Sensory neurons entering the brain from the peripheral nervous system deliver information about the condition of the body and its surroundings. Most of the neurons in the brain’s gray matter are interneurons, which are responsible for integrating and processing information delivered to the brain by sensory neurons. Interneurons send signals to motor neurons, which carry signals to muscles and glands. Neuroglia, or glial cells, act as the helper cells of the brain; they support and protect the neurons. In the brain there are four types of glial cells: astrocytes, oligodendrocytes, microglia, and ependymal cells. Astrocytes protect neurons by filtering nutrients out of the blood and preventing chemicals and pathogens from leaving the capillaries of the brain. Oligodendrocytes wrap the axons of neurons in the brain to produce the insulation known as myelin. Myelinated axons transmit nerve signals much faster than unmyelinated axons, so oligodendrocytes accelerate the communication speed of the brain. Microglia act much like white blood cells by attacking and destroying pathogens that invade the brain. Ependymal cells line the capillaries of the choroid plexuses and filter blood plasma to produce cerebrospinal fluid. The tissue of the brain can be broken down into two major classes: gray matter and white matter. Gray matter is made of mostly unmyelinated neurons, most of which are interneurons. The gray matter regions are the areas of nerve connections and processing. White matter is made of mostly myelinated neurons that connect the regions of gray matter to each other and to the rest of the body. Myelinated neurons transmit nerve signals much faster than unmyelinated axons do. The white matter acts as the information highway of the brain to speed the connections between distant parts of the brain and body. Now let’s begin exploring the main structures of our awesome human brain. HINDBRAIN (RHOMBENCEPHALON) Brainstem Connecting the brain to the spinal cord, the brainstem is the most inferior portion of our brain. Many of the most basic survival functions of the brain are controlled by the brainstem. The brainstem is made of three regions: the medulla oblongata, the pons, and the midbrain. A net-like structure of mixed gray and white matter known as the reticular formation is found in all three regions of the brainstem. The reticular f

What makes up 60-70% of human body weight?

Water properties: The water in you (Water Science School)   Back to previous page The water in you Think of what you need to survive, really just survive. Food? Water? Air? Facebook? Naturally, I'm going to concentrate on water here. Water is of major importance to all living things; in some organisms, up to 90% of their body weight comes from water. Up to 60% of the human adult body is water. According to H.H. Mitchell, Journal of Biological Chemistry 158, the brain and heart are composed of 73% water, and the lungs are about 83% water. The skin contains 64% water, muscles and kidneys are 79%, and even the bones are watery: 31%. Each day humans must consume a certain amount of water to survive. Of course, this varies according to age and gender, and also by where someone lives. Generally, an adult male needs about 3 liters per day while an adult female needs about 2.2 liters per day. Some of this water is gotten in food. Water serves a number of essential functions to keep us all going: A vital nutrient to the life of every cell, acts first as a building material. It regulates our internal body temperature by sweating and respiration The carbohydrates and proteins that our bodies use as food are metabolized and transported by water in the bloodstream; It assists in flushing waste mainly through urination acts as a shock absorber for brain, spinal cord, and fetus forms saliva lubricates joints According to Dr. Jeffrey Utz, Neuroscience, pediatrics, Allegheny University, different people have different percentages of their bodies made up of water. Babies have the most, being born at about 78%. By one year of age, that amount drops to about 65%. In adult men, about 60% of their bodies are water. However, fat tissue does not have as much water as lean tissue. In adult women, fat makes up more of the body than men, so they have about 55% of their bodies made of water. Thus: Babies and kids have more water (as a percentage) than adults. Women have less water than men (as a percentage). People with more fatty tissue have less water than people with less fatty tissue (as a percentage). There just wouldn't be any you, me, or Fido the dog without the existence of an ample liquid water supply on Earth. The unique qualities and properties of water are what make it so important and basic to life. The cells in our bodies are full of water. The excellent ability of water to dissolve so many substances allows our cells to use valuable nutrients, minerals, and chemicals in biological processes. Water's "stickiness" (from surface tension ) plays a part in our body's ability to transport these materials all through ourselves. The carbohydrates and proteins that our bodies use as food are metabolized and transported by water in the bloodstream. No less important is the ability of water to transport waste material out of our bodies. Sources and more information

What are the very narrow blood vessels which form a network between arteries and veins?

Blood vessels - human anatomy organs Blood vessels Tweet BLOOD VESSELS ANATOMY Blood vessels are responsible for the transportation of blood , made up arteries and veins, they creates pathways for the oxygenated blood to travel to their destination and pathways for the used deoxygenated blood to travel back to the heart or lungs . Capillaries are designed to permit the transfer of gasses within the blood, such as the delivery of oxygen and the return of carbon dioxide. The molecules from the tissues use the oxygenated blood plasma for energy and return the molecules of wastes. Blood vessels form these pathways to reach every living cell within the human body for this gaseous exchange. The network formed by the blood vessels is tubular, extensive, and in many ways fragile to outside influences. BLOOD VESSELS FUNCTIONS As the blood leaves the heart, they are filled with molecules of necessary oxygen, and traverse a passageway of progressively smaller tubular networks known as (in order) arteries, arterioles, and capillaries. The microscopic capillaries are responsible for the conjoining of arterial flow and venous flow. Capillaries create the environment for the actual gaseous exchange. As blood returns to the heart for more oxygen it passes through a tubular network of progressively larger diameter known as (in order) venules and veins. Anastomosis is the convergence arteries. While there are several places throughout the body where this process of anastomosis occurs, this includes the necks of the humerus and femur . Anastomosis occurs in areas that require a constant supply of oxygenated blood. BLOOD VESSELS DIAGRAM Image: Blood Vessels Blood vessels are comprised of three layers which form the tubular network. The outermost layer is comprised of connective tissue. This layer is known as either tunica externa or advetitia. The middle layer is known as tunica media and is comprised of thin muscular tissue. Throughout this stratum there are diverse amounts of elastic fibers. The inner most layer is a combination of simple squamous epithelium and elastin. The layer of squamous epithelium is termed as the endothelium. All blood vessels have this inner layer as their inner lining. BLOOD VESSELS STRUCTURE The structure of a capillary is a bit different. They have a basement membrane for support and have only a endothelium layer. Arteries and veins are nearly the same, with the exception of a few vital differences in their structure. The arteries are responsible for the transport of blood away from the heart while veins are responsible for the transport of blood back to the heart. An artery that is compared with the same sized vein is going to have more muscle in their structure. Cross section comparisons show that arteries are more circular than veins. Veins generally do not fill to capacity and therefore have a more relaxed shape. Veins have the capability to expand when filled with additional blood and make up the body’s venous reservoirs. Arteries are also devoid of valves , which veins are equipped with in their structure. ARTERIES In order for the arteries to expand when the heart fills them with blood and retract when there is absence of blood, the arteries have layers of elastic fibers in between their layers of smooth muscle in the tunica media section. The action of expanding and contracting helps create a more even and less volatile rhythmic pattern of alternating systole and diastole action in the smaller arteries and arterioles. The smaller the artery the less elastic fiber is built into their layers of muscle. This creates an even diameter in the smaller arteries. Larger arteries are designed to expand and contract with the rhythm set forth by the heart. ARTERIES FUNCTIONS The small muscular arteries are more rigid, thus they create more resistance through the circulatory system than veins or larger arteries. These small arteries have very narrow lumina, which is also the case with the small arterioles. The smallest of the arteries branch off to form the arterioles. Any artery that is less than 100 micrometers in

What is the ring of bones at the hip called?

Hip bone Anatomy | Bone and Spine You are here: Home / Anatomy / Hip bone Anatomy Hip bone Anatomy Published - By Dr Arun Pal Singh Last Edited Apr 1, 2015 @ 5:16 pm Hip bone is also known as inominate bone or pelvic bone and is formed by fusion of three bones namely ilium, ischium and pubis bones. Hip bone forms part of pelvis and takes part in hip joint articulation. The hip bone is made up of the three parts – the ilium, pubis and ischium. Prior to puberty, the triradiate cartilage separates these constituents. At the age of 15-17, the three parts begin to fuse. Their fusion forms a cup-shaped socket known as the acetabulum, which becomes complete at 20-25 years of age. The head of the femur articulates with the acetabulum to form the hip joint. Thus the hip bone has three articulations – Sacroiliac joint – articulation with sacrum Pubic symphysis – articulation with the other hip bone . Hip joint – articulation with the head of femur. Side determination of Hip Bone Acetabulum is on lateral side Obturator formen lies below the acetabulum, pubis being anterior and ischium posterior Flat expanded part, the ilium is above the acetabulum. Anatomical Position of Hip Bone Pubic tubercle and anterior superior iliac spine lie in same coronal plane . Pelvic surface of pubis is directed backwards and upwards Symphyseal surface of the body of pubis is in the median plane . Ilium Ilium is largest part of the hip bone and forms upper expanded plate in upper part and contributes to acetabulum formation in lower part. Roughly two fifth of acetabulum is contributed by ilium. Upper end of ilium is called iliac crest. Iliac crest is broad, convex, topmost portion of ilium which can be palpated in the flank area. Anterior end of iliac crest is called the anterior superior iliac spine which is a very important anatomical landmark. Iliac crest ends posteriorly in the posterior superior iliac spine [Located about dimple of venus about by a dimple 4 cm lateral to the second sacral spine. ] Iliac crest is divided in to a ventral segment and a dorsal segment which meet at the tubercle. The ventral segment forms more than the anterior two thirds of the crest. The dorsal segment forms less than the posterior one third of the crest. Lower end is fused with ischium and pubis at the acetabulum. Ilium has got three borders [anterior, posterior and medial ] and three surfaces [gluteal, iliac, and a sacropelvic surface]. Borders of Ilium Anterior border of ilium starts at the anterior superior iliac spine and runs downwards to the acetabulum. In upper part , the border has a notch and while its lower part has  anterior inferior iliac spine. Posterior border extends from the posterior superior iliac spine to the upper end of the posterior border of the ischium. It is marked by prominence called posterior inferior iliac spine and lower a large deep notch called the greater sciatic notch. Medial Border is on the inner surface of the ilium from the iliac crest to the iliopubic eminence and separates the iliac fossa from the sacropelvic surface. Its lower rounder part form the iliac part inlet of pelvis or arcuate line . Surfaces of Ilium Gluteal surface is the outer surface of the ilium, which is convex in front and concave behind. Three gluteal lines divide the gluteal surface. The posterior gluteal line is the shortest and extends from a point front of the posterior superior spine to a point of the posterior inferior spine. The anterior gluteal line is the longest , begins about an inch behind the anterior superior spine, runs backwards and then downwards to end at the middle of the upper border of the greater sciatic notch. The inferior gluteal line is not well defined. It begins a little above and behind the anterior inferior spine, runs backwards and downwards to end near the apex of the greater sciatic notch. Inner surface of ilium is divided by medial border into iliac fossa and sacropelvic surface. Iliac fossa is the large concave area on the inner surface of the ilium, situated in front of its medial border. It forms the lateral wall of the fals

What tube connects the kidney to the bladder?

KidneyStones.org Ureter Function The ureter is a thick-walled tube leading from each kidney, which carries urine to the bladder. Urine flows down partly by gravity, but mainly by a wave of contractions, called peristalsis, which pass several times per minute through the muscle layers of the urethral walls. Structure Each ureter is a tubular organ measuring about 25 centimeters (ten to twelve inches) in length beginning at the funnel-shaped renal pelvis. Within the wall of the ureter are three layers. The inner layer, or mucous coat, is continuous with the linings of the renal tubules above and the urinary bladder below. The middle layer, or the muscular coat, is composed of largely smooth muscle fibers. The outer layer, or the fibrous coat, is primarily composed of connective tissue. Each ureter enters the bladder through a tunnel in the bladder wall, which is angled to prevent the urine from running back into the ureter, known as reflux, when the bladder contracts.

What is the name of the structural tissue found in the ear, the nose, and in between the vertebral discs?

Connective Tissues: Loose, Fibrous, and Cartilage About Watch and Favorite Watch Watching this resources will notify you when proposed changes or new versions are created so you can keep track of improvements that have been made. Favorite Favoriting this resource allows you to save it in the “My Resources” tab of your account. There, you can easily access this resource later when you’re ready to customize it or assign it to your students. Connective Tissues: Loose, Fibrous, and Cartilage Connective tissue is found throughout the body, providing support and shock absorption for tissues and bones. Learning Objective Distinguish between the different types of connective tissue Key Points Fibroblasts are cells that generate any connective tissue that the body needs, as they can move throughout the body and can undergo mitosis to create new tissues. Protein fibers run throughout connective tissue, providing stability and support; they can be either collagen , elastic, or reticular fibers. Loose connective tissue is not particularly tough, but surrounds blood vessels and provides support to internal organs. Fibrous connective tissue, which is composed of parallel bundles of collagen fibers, is found in the dermis, tendons, and ligaments. Hyaline cartilage forms the skeleton of the embryo before it is transformed into bone; it is found in the adult body at the tip of the nose and around the ends of the long bones, where it prevents friction at the joints. Fibrocartilage is the strongest of the connective tissues; it is found in regions of the body that experience large amounts of stress and require a high degree of shock absorption, such as between the vertebrae. Terms Full Text Connective Tissues Connective tissues are composed of a matrix consisting of living cells and a non-living substance, called the ground substance. The ground substance is composed of an organic substance (usually a protein) and an inorganic substance (usually a mineral or water). The principal cell of connective tissues is the fibroblast, an immature connective tissue cell that has not yet differentiated. This cell makes the fibers found in nearly all of the connective tissues. Fibroblasts are motile , able to carry out mitosis, and can synthesize whichever connective tissue is needed. Macrophages , lymphocytes , and, occasionally, leukocytes can be found in some of the tissues, while others may have specialized cells. The matrix in connective tissues gives the tissue its density . When a connective tissue has a high concentration of cells or fibers, it has a proportionally-less-dense matrix. The organic portion, or protein fibers, found in connective tissues are either collagen, elastic, or reticular fibers. Collagen fibers provide strength to the tissue, preventing it from being torn or separated from the surrounding tissues. Elastic fibers are made of the protein elastin; this fiber can stretch to one and one half of its length, returning to its original size and shape. Elastic fibers provide flexibility to the tissues. Reticular fibers, the third type of protein fiber found in connective tissues, consist of thin strands of collagen that form a network of fibers to support the tissue and other organs to which it is connected. Loose (Areolar) Connective Tissue Loose connective tissue, also called areolar connective tissue, has a sampling of all of the components of a connective tissue. Loose connective tissue has some fibroblasts, although macrophages are present as well. Collagen fibers are relatively wide and stain a light pink, while elastic fibers are thin and stain dark blue to black . The space between the formed elements of the tissue is filled with the matrix. The material in the connective tissue gives it a loose consistency similar to a cotton ball that has been pulled apart. Loose connective tissue is found around every blood vessel, helping to keep the vessel in place. The tissue is also found around and between most body organs. In summary, areolar tissue is tough, yet flexible, and comprises membranes.

Which artery supplies the kidney with blood?

Blood Supply to the Kidneys - Anatomy Pictures and Information Home > Cardiovascular System > Cardiovascular System of the Lower Torso > Blood Supply to the Kidneys Blood Supply to the Kidneys Providing a constant supply of oxygenated blood to the kidneys is one of the most vital functions of the circulatory system. Despite their relatively small size, the kidneys receive about 20% of the heart’s blood output for filtration. The kidneys’ function is dependent on a constant blood supply, so interruptions in the blood flow to the kidneys may result in tissue death and loss of kidney function. Anatomy Move up/down/left/right: Click compass arrows Rotate image: Click and drag in any direction, anywhere in the frame Identify objects: Click on them in the image 2D Interactive 3D Rotate & Zoom Change Anatomical System Kidney Blood Filtration Full Blood Supply to the Kidneys Description [Continued from above] . . . In the abdomen, the renal arteries branch from the abdominal aorta inferior to the superior mesenteric artery and extend laterally toward the kidneys. Just before reaching the kidney, each renal artery divides into five segmental arteries, which provide blood to the various regions of the kidney. Each segmental artery enters the hilus of the kidney and divides into several interlobar arteries, which pass through the renal columns between the renal pyramids and carry blood toward the exterior of the kidney. At the junction between the renal cortex and renal medulla, the interlobar arteries form the arcuate arteries, which turn to follow the contours of the renal pyramids. From the arcuate arteries several branches, known as interlobular arteries, separate at right angles and extend through the renal cortex toward the exterior of the kidney. Each interlobular artery forms several afferent arterioles, which end in a bed of capillaries known as glomeruli where blood is filtered to form urine. Physiology Kidney function is highly dependent upon sufficient blood pressure in the glomeruli. The arteries and arterioles that provide blood flow to the kidneys must maintain sufficient blood flow to keep the tissues of the kidneys alive and also maintain sufficient blood pressure to allow wastes to be separated from the blood. Interruption of the blood flow through one of the segmental arteries or their branches results in kidney infarction, where kidney tissue dies and ceases to function. Interruption of the blood flow to the entire kidney results in kidney failure. While it is possible to survive with only one functional kidney, loss of both kidneys requires dialysis or a kidney transplant to filter wastes from the blood. Prepared by Tim Taylor, Anatomy and Physiology Instructor

How many ventricles are there in the human heart?

Your Heart & Circulatory System Your Heart & Circulatory System Tu corazón y sistema circulatorio Did you give your friends valentines and little heart-shaped candies on Valentine's Day? Do you ever cross your heart when making a promise that you really, really mean? Or turn on the radio to hear a guy singing about his broken heart? We see and hear about hearts everywhere. A long time ago, people even thought that their emotions came from their hearts, maybe because the heart beats faster when a person is scared or excited. Now we know that emotions come from the brain, and in this case, the brain tells the heart to speed up. So what's the heart up to, then? How does it keep busy? What does it look like? Let's find out. Working That Muscle Your heart is really a muscle. It's located a little to the left of the middle of your chest, and it's about the size of your fist. There are lots of muscles all over your body — in your arms, in your legs, in your back, even in your behind. But the heart muscle is special because of what it does. The heart sends blood around your body. The blood provides your body with the oxygen and nutrients it needs. It also carries away waste. Your heart is sort of like a pump, or two pumps in one. The right side of your heart receives blood from the body and pumps it to the lungs. The left side of the heart does the exact opposite: It receives blood from the lungs and pumps it out to the body.   We Got the Beat How does the heart beat? Before each beat, your heart fills with blood. Then its muscle contracts to squirt the blood along. When the heart contracts, it squeezes — try squeezing your hand into a fist. That's sort of like what your heart does so it can squirt out the blood. Your heart does this all day and all night, all the time. The heart is one hard worker! continue Heart Parts The heart is made up of four different blood-filled areas, and each of these areas is called a chamber. There are two chambers on each side of the heart. One chamber is on the top and one chamber is on the bottom. The two chambers on top are called the atria (say: AY-tree-uh). If you're talking only about one, call it an atrium. The atria are the chambers that fill with the blood returning to the heart from the body and lungs. The heart has a left atrium and a right atrium. The two chambers on the bottom are called the ventricles (say: VEN-trih-kulz). The heart has a left ventricle and a right ventricle. Their job is to squirt out the blood to the body and lungs. Running down the middle of the heart is a thick wall of muscle called the septum (say: SEP-tum). The septum's job is to separate the left side and the right side of the heart. The atria and ventricles work as a team — the atria fill with blood, then dump it into the ventricles. The ventricles then squeeze, pumping blood out of the heart. While the ventricles are squeezing, the atria refill and get ready for the next contraction. So when the blood gets pumped, how does it know which way to go? Well, your blood relies on four special valves inside the heart. A valve lets something in and keeps it there by closing — think of walking through a door. The door shuts behind you and keeps you from going backward. Two of the heart valves are the mitral (say: MY-trul) valve and the tricuspid (say: try-KUS-pid) valve. They let blood flow from the atria to the ventricles. The other two are called the aortic (say: ay-OR-tik) valve and pulmonary (say: PUL-muh-ner-ee) valve, and they're in charge of controlling the flow as the blood leaves the heart. These valves all work to keep the blood flowing forward. They open up to let the blood move ahead, then they close quickly to keep the blood from flowing backward. previous continue It's Great to Circulate You probably guessed that the blood just doesn't slosh around your body once it leaves the heart. It moves through many tubes called arteries and veins , which together are called blood vessels. These blood vessels are attached to the heart. The blood vessels that carry blood away from the heart are called arteries. The

What is the scientific name for the tube connecting the mouth with the stomach?

What tube connects the mouth and the stomach? | Reference.com What tube connects the mouth and the stomach? A: Quick Answer The tube that connects the mouth and the stomach is the esophagus, according to Dictionary.com. The esophagus is a muscular passage found in vertebrate and invertebrate animals. It's sometimes referred to as the "gullet." Full Answer WebMD explains that the esophagus is about 8 inches long and is located behind the heart and trachea, or windpipe, and in front of the spine. WebMD notes that the esophagus passes through the diaphragm just prior to entering the stomach. Muscles at the top of the esophagus are controlled consciously and are used during breathing, eating, vomiting, belching and in preventing food from entering the windpipe, according to WebMD. The muscles at the bottom of the esophagus are involuntary muscles, and they prevent acid and stomach contents from traveling back into the esophagus.

Which parts of the body are formed by the bones of the metatarsals and phalanges?

Bones of the Foot - Tarsals - Metatarsals - Phalanges - TeachMeAnatomy The human foot is a very complex and highly developed structure. The bones of the foot provide mechanical support for the soft tissues, helping the foot withstand the weight of the body. The bones of the foot can be divided into three categories: Tarsals – A set of seven irregularly shaped bones. They are situated proximally in the foot, in the ankle area. Metatarsals – These bones connect the phalanges to the tarsals. There are five in number – one for each digit. Phalanges – The bones of the toes. Each toe has three phalanges – a proximal, intermediate and distal (except the big toe, which only has two phalanges). Fig 1.0 – Overview of the bones of the human foot. Tarsals The tarsal bones of the foot are organised into three rows; proximal, intermediate and distal. Proximal Group The proximal tarsal bones are the talus and the calcaneus. They form the bony framework around the proximal ankle and heel area. The talus is the most superior of the tarsal bones. It has three articulations: Superiorly: Ankle joint – between the talus and the bones of the leg (the tibia and fibula). Inferiorly: Subtalar joint – between the talus and calcaneus. Anteriorly: Talonavicular joint – between the talus and the navicular. The main function of the talus is to transmit forces from the tibia to the heel bone (known as the calcaneus). Whilst numerous ligaments attach to the talus, it is not a site of muscle attachment or origin. Fig 1.1 – The tarsal bones of the foot. The calcaneus lies underneath the talus, and has two articulations: Superiorly: Subtalar joint – between the calcaneus and the talus. Anteriorly: Calcaneocuboid joint – between the calcaneus and the cuboid. It is thick and sturdy, acting to transmit forces from the talus to the ground. The posterior aspect of the calcaneus is marked by calcaneal tuberosity, to which the Achilles tendon attaches. Intermediate Group The intermediate row of tarsal bones contains one bone, the navicular (given its name because it is shaped like a boat). It articulates with the talus posteriorly, the cuneiform bones anteriorly, and the cuboid bone laterally. On the plantar surface of the navicular, there is a tuberosity for the attachment of the tibialis posterior tendon. Distal Group In the distal row, there are four tarsal bones – the cuboid and the three cuneiforms. These bones articulate with the metatarsals of the foot. The cuboid is the most lateral bone in the distal row, articulating with the calcaneus posteriorly, and two metatarsals anteriorly. As the name suggests, it is shaped like a cube. The inferior surface of the cuboid is marked by a groove for the fibularis longus muscle. The three cuneiforms (lateral, intermediate and medial) are wedge shaped bones. They articulate with the navicular posteriorly, and the metatarsals anteriorly. The shape of the bones helps form a transverse arch across the foot. Clinical Relevance: Fractures of the Talus and Calcaneus The talus and the calcaneus sit in the proximal part of the foot and ankle, and are involved in transmitting forces from the body to the ground. They are the most frequently fractured of all the tarsal bones. Talus Talar fractures occur in two places – the neck of the talus, or the body: Neck fractures are caused by excessive dorsiflexion of the foot. The neck of the talus is pushed against the tibia. In this type of fracture, the blood supply to the talus may be disturbed, leading to avascular necrosis of the bone. Body fractures usually occur from jumping from a height. In any fracture of the talus, the malleoli of the leg bones act to hold the fragments together, so there is little displacement of the fracture pieces. By Jojo (Own work) [CC-BY-SA-3.0], via Wikimedia Commons Fig 1.2 – X-ray of a calcaneal fracture. Calcaneus The calcaneus is often fractured in a ‘crush‘ type injury. The most common mechanism of damage is falling onto the heel from a height – the talus is driven into the calcaneus. The bone can break into several pieces – known as a comminuted

What is the fluid that lubricates and cushions the movable joints between the bones?

what is synovial fluid n wat is its rush? What is synovial fluid n wat is its stress? Answers: Synovial fluid is a thick, stringy fluid found contained by the cavities of synovial joint. With its egg-like consistency (synovial comes from Latin for "egg"), synovial fluid reduces friction between the articular cartilage and other tissues contained by joints to lubricate and cushion them during movement. Overview The inner membrane of synovial joint is called the synovial membrane, which secrete synovial fluid into the joint cavity. This fluid forms a sunken layer (approximately 50 micrometres) at the surface of cartilage, but also seep into the articular cartilage filling any unfilled space . The fluid within articular cartilage effectively serves as a synovial fluid reserve. During majority movements, the synovial fluid held within the cartilage is squeezed out routinely (so-called weeping lubrication) to maintain a band of fluid on the cartilage surface. more: http://en.wikipedia.org/wiki/synovial_fl... It is the fluid around closed joints, approaching the knees. It is very momentous to cushion the joint and keep hold of it lubricated and healthy. Joints that aren't roofed, like the spine, don't hold it, but are cushioned differently. Any of the sites below should have the answer you are looking for :-) http://adam.nearly.com/encyclopedia/19698... Synovial fluid is in adjectives of your freely movable joints. Elbow, Knee ,etc. It's rush is that it keeps your joint lubricated so that there is no friction. So not to mess up your bones. Synovial fluid is a viscous colourless fluid that bathe movable joints between the bones of vertebrates. It nourish and lubricates the cartilage at the end of respectively bone. The normal knees joint is surrounded by a membrane (the synovium) which produces a small amount of gooey fluid (synovial fluid). The synovial fluid helps to provide for the cartilage and keep it slippery. Synovial fluid is secreted by a membrane, the synovium, that links movably jointed bones. The same thoughtful of fluid is found in bursae, the membranous sac that buffer some joints, such as surrounded by the shoulder and hip region. Viscid lubricating fluid secreted by the membrane lining joint and tendon sheaths etc synovial common is a type of joint that allows free movements of bones..these joint r lined by a synovial membrane that secrete synovial fluid..Synovial fluid is normally a viscous (thick), straw colored substance that help in free movements of bones inwardly the joints..synovial fluid is tested surrounded by suspected joint pathologies..To gain the fluid for analysis, a sterile needle is inserted into the common space through skin that has be specially cleaned. Once in the pooled, fluid is aspirated through the needle into a sterile syringe.. It is consequently examined microscopically for cells (red and white cells), crystals (in the valise of gout), and bacteria. In assimilation, there may be a chemical analysis, and if infection is a concern, a example will be cultured to see if any bacteria grow. Abnormal cohesive fluid may look cloudy or abnormally gluey. Synovial fluid is a thick, stringy fluid found surrounded by the cavities of synovial joint. With its egg-like consistency (synovial comes from Latin for "egg"), synovial fluid reduces friction between the articular cartilage and other tissues contained by joints to lubricate and cushion them during movement. it is fluid present contained by joint contained by joint cavity.relief in lubrication of unified. synovial fluid is the fluid between your joints it keep the bones from rubbing together synovial fluid s actually fluid ie present surrounded by joints. it help as a lubricating agent for easy movement of joint without injuring the bones. synovial membrane forms the facing of the soft parts that enclose the cavity of a cohesive...the cavity has the synovial fluid it help in th lubrication of the joint.SYNOVITIS is the inflammation of the membrane lining the joint its a substance present between two joints & help in lubrication this is a flu

What is the oxygen-carrying protein found in the red blood cells of the body?

a Hemoglobins i Oxygen carrying proteins found in the red - FNH - 250 View Full Document ii. 2/3rds of irons are found here b. Myoglobins i. Oxygen-carrying proteins found in muscle cells (similar to hemoglobins) 4. What are 3 major functions of iron? a. b. Coenzyme for energy production c. Part of an antioxidant enzyme system that stabilizes free radicals 5. What are the forms we store iron as? Where is iron mainly stored? a. Ferritin and Hemosiderin b. Stored in: Liver, bone marrow, intestinal mucosal, bone marrow 6. How do the following affect absorption of iron from our diet: (a) iron status, (b) stomach acid, and (c) amount and type of iron in foods a. Iron status i. Those with lower iron status will have higher absorption of iron (see below) b. Stomach Acid i. An adequate pH of stomach is necessary for iron absorption 1. Ie. Too low pH = decrease iron absorption c. Amount and type of irons in food i. Amount 1. The more iron consumed, the lower the absorption ii. Types 1. Heme iron is more easily absorbed than non-heme iron (See below) 7. What affects iron status? a. Those that are iron deficient: pregnant women, menstruation 8. What is heme iron and what is non-heme iron? a. Heme Iron i. b. Non-heme Iron i. 9. Compare heme iron and non-heme iron in terms of their digestion and food sources a. Heme iron is more absorbable b. Food sources i. Heme Iron: 1. Animal-based foods like fish, meat, poultry ii. Non-heme iron: 1. Animal-based foods like fish, meat, poultry 2. Plant-based foods 10. Animal-based foods are better sources of iron (ie. More readily absorbable) b/c they contain more This is the end of the preview. Sign up to access the rest of the document. TERM Chapter 10- Nutrients Involved in Energy Metabolism.docx UBC FNH 250 - Winter 2014 1. Vitamins and minerals do not provide us with energy. What do they do? a. Are coenz Chapter 10- Nutrients Involved in Energy Metabolism.docx

What are the chemicals produced by the endocrine glands to control body functions?

Hormones: the body’s chemical messengers | Visual Dictionary Subscribe Hormones: the body’s chemical messengers The human body secretes and circulates some 50 different hormones. A wide variety of these chemical substances are produced by endocrine cells, most of which are in glands. The hormones then enter the blood system to circulate throughout the body and activate target cells. The endocrine system, tightly linked to the nervous system , controls a large number of the body’s functions: metabolism, homeostasis, growth, sexual activity, and contraction of the smooth and cardiac muscles. The endocrine glands The endocrine system is composed of nine specialized glands (the pituitary, the thyroid, the four parathyroids, the two adrenals and the thymus) and a number of organs capable of producing hormones (including the pancreas , heart , kidneys , ovaries , testicles and intestines). The hypothalamus , which is not a gland but a nerve center, also plays a major role in the synthesis of hormonal factors. The endocrine system The hypothalamus and the pituitary gland: the control centers of the endocrine system Located under the thalamus, the hypothalamus is composed of several nuclei that control the autonomic nervous system and regulate hunger, thirst, body temperature and sleep. The hypothalamus also influences sexual behavior and controls the emotions of anger and fear. Closely linked to the pituitary gland , it acts as a coordinator between the nervous and endocrine systems. Generally considered the master endocrine gland, the pituitary secretes 10 different hormones. Some of these substances then act on the other endocrine glands. Unlike substances produced by the exocrine glands, which flow through ducts, the hormones are released directly into the space that surrounds them by secreting cells. The very high vascularization of endocrine glands enables hormones to spread throughout the blood system via the capillaries. Some of them circulate freely in the blood, while others must attach to carrier proteins to reach the target cells.

Where in the human body do you find the alveoli?

The role of Alveoli in the respiratory system Home / Training Zone / The Human Body / Respiratory System / Alveoli Alveoli Part of the respiratory system, these tiny alveoli have a key role in the movement of oxygen and carbon dioxide. Role in the respiratory system. The final branches of the respiratory tree, alveoli are where oxygen from the air enters your blood, and carbon dioxide from your body is expelled back into the air. How they work. Air enters the body through the nose or mouth, passes through the larynx, down the trachea, and into our lungs. Once it is in your lungs, air goes through a maze of smaller and smaller bronchial tubes until it reaches clusters of tiny sacs the alveoli. In appearance they are somewhat like bunches of grapes. Size and where they live. These alveoli are tiny, but your lungs are simply packed with them an estimated three hundred million per lung, all required to ensure that your body gets the oxygen it needs. Once it is in your lungs, the blood has to get into your blood. The alveoli are the primary gas exchange units of the lung. Quite simply, they are the point where the gas-blood barrier is thin enough to permit rapid gas exchange. To get into the blood, oxygen is diffused through the alveolar epithelium, a thin interstitial space, and the capillary endothelium. Role also has to be reversed. That is only half the process of course this process also has to work in reverse in order to allow CO2, a waste product carried by the blood, to be expelled back into the lungs, and thus out of the body when we exhale.

What name is given to the genetic make-up of an individual?

A genotype is the genetic make up of an individual Pearson - BIO - 1100 View Full Document Name ______Bennett_ ____ Page 2 of 7 Heredity 4. Explain Mendel’s “law” of “independent assortment”. When does it occur during cell division? Mendel’s law of independent assortment states that each pair of factors assorts independently of the other pairs and that all possible combinations of factors can occur in the gametes. (Mader and Windelspecht) This means that the genes from one trait separate independently from the genes of another trait allowing for multiple different outcomes. Independent assortment occurs in meiosis I, specifically in prophase I. 5. Explain Mendel’s “law” of “segregation”. Give an example. Mendel’s law of segregation states that each individual has two factors for each trait and that these factors separate during the formation of gametes. Each gamete then contains only one gene from each pair of genes. Fertilization then gives each new individual two genes for each trait. (Mader and Windelspecht) An example of the law of segregation is shown in the lab when the genes from a tall pea plant are combined with the genes of a dwarf pea plant resulting in the separation of the gametes and allowing for either a tall pea plant or dwarf pea plant as offspring. Genetics Problem Involving a Monohybrid Cross Possible Points 4 Points Deducted Add a row or column to the tables if necessary. 6. A plant that is heterozygous (Pp) for purple flowers is crossed with a plant that is also heterozygous (Pp) for purple flowers. What will be the genotypes and phenotypes of the F 1 generation? Type the possible gene combinations in the Punnett square and then type the genotype and phenotype ratios in the table below the Punnett square. P = purple flowers (dominant) p = white flowers (recessive) P p P PP Pp p Pp pp Genotypes Phenotypes of Flower Colors # of Each Phenotype (data taken from Punnett square) Ratios of Phenotypes PP Homozygous dominant 1 1:4 Purple flowers Purple flowers Name ______Bennett_ ____ Page 3 of 7 Heredity Pp Heterozygous 2 1:2 pp Homozygous recessive 1 1:4 Testcross Problem to Determine Unknown Genotypes Possible Points 4 Points Deducted Add a row or column to the tables if necessary. 7. This preview has intentionally blurred sections. Sign up to view the full version.

A bone is joined to a muscle by which structure?

Muscular and Skeletal Systems MUSCULAR AND SKELETAL SYSTEMS Interaction of the Two Systems | Links The single-celled protozoan ancestors of animals had their weight supported by water and were able to move by cilia or other simple organelles. The evolution of large and more complex organisms (animals) necessitated the development of support and locomotion systems. Animals use their muscular and skeletal systems for support, locomotion, and maintaining their shape. Types of Skeletal Systems | Back to Top Movement is a major characteristic of animals. This movement is a result of contraction of muscles. The skeleton helps transmit that movement. Skeletons are either a fluid-filled body cavity, exoskeletons , or internal skeletons. Hydrostatic skeletons consist of fluid-filled closed chambers. Internal pressures generated by muscle contractions cause movement as well as maintain the shape of the animals, such as the sea anemone and worms. The sea anemone has one set of longitudinal muscles in the outer layer of the body, and a layer of circular muscles in the inner layer of the body. The anemone can elongate or contract its body by contracting one or the other set of muscles. Structure and function of a hydrostatic skeleton. Images from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates ( www.sinauer.com ) and WH Freeman ( www.whfreeman.com ), used with permission. Exoskeletons are characteristic of the Phylum Arthropoda. Exoskeletons are hard segments that cover the muscles and visceral organs. Muscles for movement attach to the inner surface of the exoskeleton. Exoskeletons restrict the growth of the animal, thus it must shed its exoskeleton (or molt) to form a new one that has room for growth. The bulk and weight of the exoskeleton and associated mechanical problems limits the size animals can attain. Spiders use a combination of an exoskeleton for protection and fluid pressure for movement. Exoskeleton of an insect and its relation to the muscular system. Image from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates ( www.sinauer.com ) and WH Freeman ( www.whfreeman.com ), used with permission. Vertebrates have developed an internal mineralized (in most cases) endoskeleton composed of bone and/or cartilage. Muscles are on the outside of the endoskeleton. Cartilage and bone are types of connective tissue . Sharks, and rays have skeletons composed entirely of cartilage; other vertebrates have an embryonic cartilage skeleton progressively replaced by bone as they mature and develop. Some areas of the human body, however, retain cartilage in the adult: in joints and flexible structures such as the ribs, trachea, nose and ears. The human endoskeleton. Image from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates ( www.sinauer.com ) and WH Freeman ( www.whfreeman.com ), used with permission. Functions of Muscles and Bones | Back to Top The skeleton and muscles function together as the musculoskeletal system. This system (often treated as two separate systems, the muscular , and skeletal ) plays an important homeostatic role: allowing the animal to move to more favorable external conditions. Certain cells in the bones produce immune cells as well as important cellular components of the blood. Bone also helps regulate blood calcium levels, serving as a calcium sink. Rapid muscular contraction is important in generating internal heat, another homeostatic function. The Axial and Appendicular Skeletons | Back to Top The axial skeleton consists of the skull, vertebral column, and rib cage. The appendicular skeleton contains the bones of the appendages (limbs, wings, or flippers/fins), and the pectoral and pelvic girdles . The human skull, or cranium , has a number of individual bones tightly fitted together at immovable joints . At birth many of these joints are not completely sutured together as bone, leading to a number of "soft spots" or fontanels , which do not completely join until the age of 14-18 months. The vertebral column has 33 individ

What is the biggest bone in the body?

Human Bones: Largest Bone in Body of Humans Information of the world Home » English » Pair of Words » Human Bones: Largest Bone in Body of Humans Bones are very important to give shape to the body, which raises the question which is being the largest bone in the human body. The size and the diameter of the bone depend on the health, height and sex of a person. The size of the biggest bone in human body of a tall man would be different from a man of an average size. Similarly the size and the thickness of different bones in men and women, whether of same height, would also be different. Keeping a single global size as standard, the details of the biggest and the longest bones are: Femur is the largest bone in body . It forms the upper part of human leg. Its average length in adult male is 50.50 centimeter. This bone is also found in mammals, reptiles and vertebrates i.e frog, lizards, amphibians etc. Femur is Latin word which means thigh hence it is also known as thigh bone. Tibia is the second largest bone in the human body and no doubt the strongest bone of human body because it bears the body weight of person. It forms the inner-lower part of human leg. The average length of tibia is 43.03 CM. Tibia is Latin word which means an ancient type of musical instrument. Shin bone and shank bone are other names of Tibia. Fibula (also known as Calf Bone) is located in the outer-lower part of human leg. Fibula is the third largest bone in the human body. Fibula along with Tibia forms the lower part of human leg as it is located on the lateral side of Tibia. It is relatively weak and thin as compared with Tibia. The average length of tibia is 40.50 CM. Humerus bone connects shoulder with elbow in human arm. It is a long bone which consists of three parts i.e. upper extremity of Humerus, body of Humerus and lower extremity of Humerus. Humerus forms the upper part of human arm and many important muscles are attached with it. The average length of tibia is 36.46 CM. Ulna forms the inner-lower part of human arm. This fore-arm bone along with radius completes the lower part of human arm. Its average length in 28.20 Cm. In simple words it connects elbow with hand. It is a long and narrow bone with many muscles attached with it. Radius is a long bone which forms the outer-lower part of human arm. It is on the lateral side of Ulna and its length is 26.42 cm. Radius is also found in some four-leg animals as lower part of forelimb. Like Ulna it connects hand with elbow. 7th rib is part of the 24 ribs found in a human body. The average length of 7th rib is 24.00 CM. Ribs are basically found in Vertebrates and they support the upper body of vertebrates. 8th rib: These long and curved bones are considered as the basic structural part of human body. 8th rib is the part of 12 pairs of ribs in human body. The average length of 8th rib is 23.00 CM. Innominate bone is also called hipbone or half pelvis. It is the 9th largest bone in human body. Its average length is 18.50 Cm. Innominate bone is either of the two bones that form the sides of the pelvis, consisting of three fused components, the ilium, ischium, and pubis Nontechnical name hipbone. Sternum is the tenth largest bone in human body and its average length is 17.00 Cm. It is also called breastbone and it is found in both males and females with the same length. Sternum is a long, flat bone located in the center of the chest, serving as a support for the collarbone and ribs.

Which of the retina's cells can distinguish between different wavelengths of light?

Molecular Expressions Microscopy Primer: Physics of Light and Color - Human Vision and Color Perception Movie Gallery Human Vision and Color Perception Human stereo color vision is a very complex process that is not completely understood, despite hundreds of years of intense study and modeling. Vision involves the nearly simultaneous interaction of the two eyes and the brain through a network of neurons, receptors, and other specialized cells. The first steps in this sensory process are the stimulation of light receptors in the eyes, conversion of the light stimuli or images into signals, and transmission of electrical signals containing the vision information from each eye to the brain through the optic nerves. This information is processed in several stages, ultimately reaching the visual cortices of the cerebrum. The human eye is equipped with a variety of optical components including the cornea, iris, pupil, aqueous and vitreous humors, a variable-focus lens, and the retina (as illustrated in Figure 1). Together, these elements work to form images of the objects that fall into the field of view for each eye. When an object is observed, it is first focused through the convex cornea and lens elements, forming an inverted image on the surface of the retina, a multi-layered membrane that contains millions of light-sensitive cells. In order to reach the retina, light rays focused by the cornea must successively traverse the aqueous humor (in the anterior chamber), the crystalline lens, the gelatinous vitreous body, and the vascular and neuronal layers of the retina before they reach the photosensitive outer segments of the cone and rod cells. These photosensory cells detect the image and translate it into a series of electrical signals for transmission to the brain. Despite some misconceptions due to the wide spectrum of terminology employed for describing eye anatomy, it is the cornea, not the lens, which is responsible for the major part of the total refractive power of the eye. Being smooth and clear as glass, yet as flexible and durable as plastic, the anterior, strongly curved, transparent part of the exterior wall of the eyeball allows the image-forming light rays to pass through to the interior. The cornea also protects the eye by providing a physical barrier that shields the inside of the eye from microorganisms, dust, fibers, chemical, and other harmful materials. Although much thinner in width than the crystalline lens, the cornea provides about 65 percent of the eye's refractive power. Most of the power to bend light resides near the center of the cornea, which is rounder and thinner than the peripheral portions of the tissue. As the window that controls the entry of light into the eye, the cornea (Figure 2) is essential to good vision and also acts as an ultraviolet light filter. The cornea removes some of the most damaging ultraviolet wavelengths present in sunlight, thereby further protecting the highly susceptible retina and crystalline lens from damage. If the cornea is curved too much, as in the case of nearsightedness, distant objects will appear as blurry images, because of imperfect light refraction to the retina. In a condition known as astigmatism, imperfections or irregularities in the cornea result in unequal refraction, which creates distortion of images projected onto the retina. Unlike most tissues of the body, the cornea does not contain blood vessels for nourishment or to protect it against infection. Even the smallest capillaries would interfere with the precise refraction process. The cornea receives its nourishment from tears and the aqueous humor, which fills the chambers behind the structure. The outer epithelial layer of the cornea is packed with thousands of small nerve endings, making the cornea extremely sensitive to pain when rubbed or scratched. Comprising about 10 percent of the tissue's thickness, the epithelial layer of the cornea blocks foreign matter from entering the eye while providing a smooth surface for oxygen and nutrient absorption. The central layer o

Which hormone causes male sexual development?

Male Hormones About Watch and Favorite Watch Watching this resources will notify you when proposed changes or new versions are created so you can keep track of improvements that have been made. Favorite Favoriting this resource allows you to save it in the “My Resources” tab of your account. There, you can easily access this resource later when you’re ready to customize it or assign it to your students. Male Hormones The onset of puberty is controlled by two major hormones: FSH initiates spermatogenesis and LH signals the release of testosterone. Learning Objective Explain the function of male hormones in reproduction Key Points The onset of puberty is signaled by high pulses of GnRH secreted by the hypothalamus ; this in turn signals the release of FSH and LH from the pituitary gland . FSH causes the Sertoli cells of the testes (which help nurse developing sperm cells) to begin the process of spermatogenesis in the testes. LH triggers the production of testosterone from the Leydig cells of the testis; testosterone causes the development of secondary sex characteristics in the male. As spermatogenesis and testosterone production increase, the Sertoli cells produce inhibin , which, together with rising levels of testosterone, inhibit the release of FSH and LH from the pituitary gland. Terms Male Hormones Puberty is a period of several years in which rapid physical growth and psychological changes occur, culminating in sexual maturity. The average onset of puberty is age 11 or 12 for boys. Some of the most significant parts of pubertal development involve distinctive physiological changes in individuals' height, weight, body composition, and circulatory and respiratory systems. These changes are largely influenced by hormonal activity. Hormones play an organizational role, priming the body to behave in a certain way once puberty begins, and an activational role, referring to changes in hormones during adolescence that trigger behavioral and physical changes. At the onset of puberty, the hypothalamus begins secreting high pulses of GnRH, or gonadotropin-releasing hormone . In response, the pituitary gland releases follicle stimulating hormone (FSH) and luteinizing hormone (LH) into the male system for the first time. FSH enters the testes, stimulating the Sertoli cells, which help to nourish the sperm cells that the testes produce, to begin facilitating spermatogenesis. LH also enters the testes, stimulating the interstitial cells, called Leydig cells, to make and release testosterone into the testes and the blood. Testosterone, the hormone responsible for the secondary sexual characteristics that develop in the male during adolescence, stimulates spermatogenesis, or the process of sperm production in the testes. Secondary sex characteristics include a deepening of the voice, the growth of facial, axillary, and pubic hair, and the beginnings of the sex drive. A negative feedback system occurs in the male with rising levels of testosterone acting on the hypothalamus and anterior pituitary to inhibit the release of GnRH, FSH, and LH . The Sertoli cells produce the hormone inhibin, which is released into the blood when the sperm count is too high. This inhibits the release of GnRH and FSH, which will cause spermatogenesis to slow down. If the sperm count reaches 20 million/ml, the Sertoli cells cease the release of inhibin, allowing the sperm count to increase.

Which part of the brain controls the heart rate?

What Parts of the Brain Control Respiration - Interactive Biology, with Leslie Samuel What Parts of the Brain Control Respiration Shares 22 The different parts of the brain with emphasis on the Medulla Oblongata First off, lets talk about what respiration is. In order for you to live, your body needs oxygen. Cell s use this oxygen in order for metabolism to take place and without it, you would have no energy. When you eat, that food is broken down and the process of respiration allows for you to convert that food into an energy form that can be used by your body. In addition to providing the body with Oxygen, it’s also responsible for getting rid of Carbon Dioxide, which is a waste product that is made in the body. Now that we have that covered, let’s talk about the involvement of the brain in this process. Your brain starts where the spinal cord enters the skull, and the first section that you encounter is called the Brain Stem. The brain stem contains the following structures: The medulla oblongata (I love that name) The Pons The Midbrain The medulla oblongata is involved in regulating many of the bodily processes that are controlled automatically like blood pressure, heart rate and yes, you guessed it . . . RESPIRATION. The way this works is relatively straightforward. The medulla oblongata basically detects carbon dioxide (CO2) and Oxygen (O2) levels in the bloodstream and determines what changes need to happen in the body. It can then send nerve impulses to muscle s in the heart and diaphragm , letting them know that they need to either step up their game, or slow down a bit. The reason I mentioned the heart is because the respiratory system is very much tied to  the circulatory system. What Happens During Exercise Lifting Weights 🙂 When you are exercising, you are using your muscle s in a significant way, and your body demands that you take in more oxygen so that it can be delivered to your muscle s. You circulatory and respiratory system needs to make sure that the oxygen is getting to the muscle s faster than when you are just chilling. Also, they need to make sure that the CO2 that is produced is taken away efficiently. In order for that process to happen efficiently, the medulla oblongata , after sensing what is happening, sends signals to the heart and the respiratory muscle s ( diaphragm and intercostal muscle s). You start breathing heavily (increased respiration) to get that O2 in and CO2 out. You heart starts beating faster because not only does the oxygen need to get into the body, but they need to be delivered to the muscle s. That gives you a pretty good idea of how the medulla oblongata controls the process of respiration. The main concept here is that there needs to be a good balance of things happening in your system in terms of respiration. If your cell s have what they need, your cell s are happy. If they are happy, your body is happy, and hopefully so are you. Questions or Comments? If you have any questions or comments about how this process works, or what I’ve written here, please post them below in the comments section. Infographic

What is an overgrowth of fibrous tissue, usually produced at the site of a scar?

Keloid Scar of Skin: Symptoms, Causes, and Treatments Keloid Scar of Skin Email addresses will not be shared with 3rd parties. See privacy policy Thank you. Your message has been sent. OK We're sorry, an error occurred. We are unable to collect your feedback at this time. However, your feedback is important to us. Please try again later. Close Key points Keloids are smooth, hard, benign growths that form when scar tissue grows excessively. Risk factors include being of African, Asian, or Latino heritage, being pregnant, and being younger than 30 years old. Treatments for keloid scarring are not always effective. When skin is injured, fibrous tissue, called scar tissue, forms over the wound to repair and protect the injury. In some cases, scar tissue grows excessively, forming smooth, hard growths called keloids. Keloids can be much larger than the original wound. They’re most commonly found on the chest, shoulders, earlobes, and cheeks. However, keloids can affect any part of the body. Although keloids aren’t harmful to your health, they may create cosmetic concerns. Picture What symptoms are associated with keloids? Keloids occur from the overgrowth of scar tissue. Symptoms occur at a site of previous skin injury. The symptoms of keloids can include: a localized area that is flesh-colored, pink, or red in color a lumpy or ridged area of skin that’s usually raised an area that continues to grow larger with scar tissue over time an itchy patch of skin Keloid scars tend to be larger than the original wound itself. They may take weeks or months to develop fully. While keloid scars may be itchy, they’re usually not harmful to your health. You may experience discomfort, tenderness, or possible irritation from your clothing or other forms of friction. In rare instances, you may experience keloid scarring on a significant amount of your body. When this occurs, the hardened, tight scar tissue may restrict your movements. Keloids are often more of a cosmetic concern than a health one. You may feel self-conscious if the keloid is very large or in a highly visible location, such as an earlobe or on the face. Sun exposure or tanning may discolor the scar tissue, making it slightly darker than your surrounding skin. This can make the keloid stand out even more than it already does. Keep the scar covered when you’re in the sun to prevent discoloration. What causes the condition? being pregnant being younger than 30 Keloids tend to have a genetic component, which means you’re more likely to have keloids if one or both of your parents has them. According to a study conducted at Henry Ford Hospital in Detroit, Michigan, a gene known as the AHNAK gene may play a role in determining who develops keloids and who doesn’t. The researchers found that people who have the AHNAK gene may be more likely to develop keloid scars than those who don’t. If people have known risk factors for developing keloids, they may want to avoid getting body piercings, unnecessary surgeries, or tattoos. When to seek medical attention Keloids typically don’t require medical attention, but you may want to contact your doctor if growth continues, you develop additional symptoms, or you want to have the keloids surgically removed. Keloids are benign, but uncontrolled growth may be a sign of skin cancer. After diagnosing keloid scarring by visual exam, your doctor may want to perform a biopsy to rule out other conditions. This involves taking a small sample of tissue from the scarred area and analyzing it for cancerous cells. Find a Doctor How is the condition treated? The decision to treat a keloid can be a tricky one. Keloid scarring is the result of the body’s attempt to repair itself. After removing the keloid, the scar tissue may grow back again, and sometimes it grows back larger than before. Examples of keloid treatments include: corticosteroid injections to reduce inflammation moisturizing oils to keep the tissue soft using pressure or silicone gel pads after injury freezing the tissue to kill skin cells laser treatments to reduce scar tissue radiation to shrink

Which is the only vein in the body to carry oxygenated blood?

Why does the pulmonary vein carry oxygenated blood instead of de-oxygenated blood? - Quora Why does the pulmonary vein carry oxygenated blood instead of de-oxygenated blood? Written Sep 12, 2015 The idea that veins only carry deoxygenated blood is an oversimplification and it's clearly not completely true. That's not what makes a vein a vein. Veins are less muscular than arteries, carry blood back toward the heart from the body, and contain valves. The pulmonary vein carries oxygenated blood because it is carrying blood back from the lungs, where it picked up oxygen. Written Sep 19, 2015 The definition of a vein is that it brings blood back towards the heart, and it so happens that blood coming back to the heart from the lungs are filled with oxygen, which is exactly what lungs were meant to do. The same goes for umbilical veins that actually carry oxygenated blood from the placenta back to the growing foetus. And since the flow back to the heart is usually passive (i.e. not pumped), veins have other common characteristics such as having thinner walls (because of lower pressures), valves (preventing reflux), are compressible, etc.

Which human body organ weighs about 2 kilos?

≡ List of Human Organs + All Sizes, Functions, Tasks, Weights & Facts 23.8 Over the skeleton around the body At up to 1.95 square meters (21 sq ft) The “derma” is the largest of all human organs and one of the heaviest weighing between 6-10% of body weight. Oil glands stop skin drying out. Skin cells are continuously shedded and replaced. Skin is a versatile organ with an ideal pH value of 5.5. Responds to external stimuli (touch, heat) and uses sweat to cool the body and raised hairs (goosebumps) to trap heat and warm the body regulating the overall temperature. Protects us from UV radiation and injury by producing thick skin (calluses). Liver 3.1 Upper right abdominal cavity just beneath the diaphragm Largest gland in the body. The “Iecur” or “hepar” has a soft smooth surface, left and right lobes and weighs between 1.4-2 kg (3-4.4 lbs). The tissue consists of around 100,000 lobules. Stores energy reserves ( vitamins and carbohydrates), detoxifies and breaks down nutrients, produces vital proteins (clotting factors). Brain 3.0 Inside the skull The female “cerebrum” weighs around 1.2 kg (2.8 lbs) compared to 1.4 kg (3 lbs) for males. The brain consumes between 20-25% of our total energy intake. The brain consists of 100 billion neurons (somata) and 100 trillion synapses. The neural pathways are 5.8 km (3.6 miles) long in total. We distinguish between: cerebrum, cerebellum, diencephalon and trunk. Processes sensory inputs, coordinates behavior and saves information; cerebrum (perception, thinking, acting), diencephalon (feelings like love, fear, anger etc.), cerebellum (balance while walking, running, dancing etc). Lungs 2.4 Inside chest rib cage The “pulmo” typically weighs just over 1kg (2.2 lbs) and has a volume between 5-6 liters (10.5-12.7 US pints) with 400 million alveoli. The (smaller) left lung consists of two lobes, the right one of three lobes. Gas exchange between air and bloodstream. In other words absorption of oxygen and release of carbon dioxide from the body. Heart 0.8 Under ribcage between your left and right lungs The “cor” or “cardia” is a fist-sized, hollow, muscular human organ weighing between 300-350g (10-12 oz), the right and left side of the heart each consist of a chamber and an atrium. Of all the human organs the heart is most impressive. At rest it can pump 4.9 liters of blood per minute through our veins. Under duress this can rise to between 20-25 liters of blood per minute. Kidney 0.7 Under ribcage in lower back Both kidneys (“ren” or “nephros”) weigh about 300 g (10½ oz). Between them the 1.2 million renal corpuscles filter up to 1500 liters (400 US gallons) of blood daily. Purifies the blood and filters out toxins from the body, controls the water balance of the body, excretion of waste products through urine production. Spleen 0.4 Below rib cage on your left side The spleen is about the size of a fist and weighs between 150 and 200 grams (5-7 oz). It’s located on the abdomen on the left kidney and below the diaphragm. Produces red and white blood cell pulp helping the immune system fight infections. Pancreas 0.22 Behind stomach in abdomen Wedge shaped organ between 16-20 cm long, 3-4 cm wide and up to 2 cm (3/4″) thick. Weighs around 100 grams (3½ oz). The pancreas is a dual function organ which produces enzymes to digest our stomach contents, separating fats, proteins and carbs. The pancreas also regulates blood sugar by producing two hormones, insulin and glucagon which have opposite effects. Thyroid 1.65 Immediately above and behind the pubic bone The “vesica urinaria” holds up to 550 ml (1.2 US pints) of urine (or with some men even up to 750 ml (1.6 US pints) Ureters connect the kidneys to the bladder and transport the purified blood (urine) to the bladder. Stores the urine resulting from the blood purification in the kidneys and removes all toxins (urea, chlorides, sodium, potassium, creatine, bicarbonate, uric acid) from the body through excretion. Blood   In blood vessels (arteries, veins, capillaries etc.) An average 5-7 liters (10.6-14.8 US pints) of “Sanguis” flows through ou

Which name is given to the heart chamber which receives blood?

Chambers of the Heart Chambers of the heart Chambers of the heart The heart has four chambers: two atria and two ventricles. The right atrium receives oxygen-poor blood from the body and pumps it to the right ventricle. The right ventricle pumps the oxygen-poor blood to the lungs . The left atrium receives oxygen-rich blood from the lungs and pumps it to the left ventricle. The left ventricle pumps the oxygen-rich blood to the body. Credits Primary Medical ReviewerWilliam H. Blahd, Jr., MD, FACEP - Emergency Medicine Adam Husney, MD - Family Medicine Specialist Medical ReviewerDavid Messenger, MD H. Michael O'Connor, MD - Emergency Medicine Martin J. Gabica, MD - Family Medicine Current as ofOctober 1, 2015 WebMD Medical Reference from Healthwise This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.© 1995-2015 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated. Top Picks

What kind of joint is the hip?

Hip Joint - Anatomy Pictures and Information Hip Joint Home > Skeletal System > Bones of the Leg and Foot > Hip Joint Hip Joint The hip joint is one of the most important joints in the human body. It allows us to walk, run, and jump. It bears our body’s weight and the force of the strong muscles of the hip and leg. Yet the hip joint is also one of our most flexible joints and allows a greater range of motion than all other joints in the body except for the shoulder. The hip joint is a ball-and-socket synovial joint formed between the os coxa (hip bone) and the femur. A round, cup-shaped structure on the os coax, known as the acetabulum, forms the socket for the hip joint. The rounded head of the femur... Move up/down/left/right: Click compass arrows Rotate image: Click and drag in any direction, anywhere in the frame Identify objects: Click on them in the image 2D Interactive 3D Rotate & Zoom Change Anatomical System Full Hip Joint Description [Continued from above] . . . forms the ball of the joint. Hyaline cartilage lines both the acetabulum and the head of the femur, providing a smooth surface for the moving bones to glide past each other. Hyaline cartilage also acts as a flexible shock absorber to prevent the collision of the bones during movement. Between the layers of hyaline cartilage, synovial membranes secrete watery synovial fluid to lubricate the joint capsule. Surrounding the hip joint are many tough ligaments that prevent the dislocation of the joint. The strong muscles of the hip region also help to hold the hip joint together and prevent dislocation. Functionally, the hip joint enjoys a very high range of motion. The ball-and-socket structure of the joint allows the femur to circumduct freely through a 360-degree circle. The femur may also rotate around its axis about 90 degrees at the hip joint. Only the shoulder joint provides as high of a level of mobility as the hip joint. In addition to being flexible, each hip joint must be capable of supporting half of the body’s weight along with any other forces acting upon the body. During running and jumping, for example, the force of the body’s movements multiplies the force on the hip joint to many times the force exerted by the body’s weight. The hip joint must be able to accommodate these extreme forces repeatedly during intense physical activities. If a knee or hip joint breaks in an accident or wears out in old age, a surgeon can replace it with a ball-and-socket joint made from metal and plastic and engineered in such a way that it will duplicate the motions of a human joint. Hip replacement was once impossible because, although joints could easily be produced in a laboratory, the human body rejected the materials. Sometimes the pins that held the artificial joint to other bones worked loose and required further surgery. Some joints, especially the artificial knee, didn't work very well because they were designed like hinges that just opened one way. Later, when the designers realized the knee needed to rotate slightly, they produced a joint that would fulfill these movements as well. Medical pioneers finally overcame bodily rejection by making the joints out of non-irritating, man-made materials. Surgeons have now perfected hip and knee replacement surgeries so that recipients are relieved of pain and can walk at a smoother pace. Prepared by Tim Taylor, Anatomy and Physiology Instructor

Where is the sinoatrial node?

The Sinoatrial Node | Pacemaker of the heart Sinoatrial Node The SA node (sinoatrial node) is a collection of tissue located in the hearts right atrium. This tissue, like all of the cells in the heart, is capable of producing electrical impulses. The unique function of the SA node however, is that it acts as the pacemaker for the heart. For a normal heart, the SA node initiates an electrical impulse causing the heart to beat. This is why a normal heart rhythm is known as a Sinus rhythm. In the event that the sinoatrial node does not work, the heart is very resilient, and will use the AV node as the primary pacemaker. If the AV node also fails, then the Purkinje cells will function as the hearts pacemaker. When the SA node is not functioning correctly, though the hearts rate may be controlled by either the AV node or the Purkinje cells, the heart rate will typically be abnormal. There are a number of arrhythmias that can be attributed to a problem with the SA node. Commonly you may see sinus bradycardia or sinus tachycardia. There are also a number of heart block issues that may be attributed to issues with the sinus node. These heart block issues include; SA node Wenckebach, SA node Mobitz II, and SA node exit block. Issues associated with the SA node can usually be diagnosed with an electrocardiogram, which is looking at the hearts electrical function. When the SA node can no longer effectively act as the pacemaker for the heart, an artificial pacemaker may be used to control the hearts electrical system. Advanced Cardiac Life Support ( ACLS ) looks at the various conditions that can affect the SA node, and deals with diagnosis, treatment paths, and pharmacology for these various conditions. Most medical professionals that deal with the cardiovascular system, or function as emergency response have ACLS certification , to ensure they can properly deal with SA node and other heart problems. The SA node is both controlled and influenced by both the parasympathetic nervous system and the sympathetic nervous system. This control/influence can adjust both the heart rate, and force of contractions. So while the heart beat occurs without conscious effort, it can also be influenced by your surroundings. For example, your heart rate will increase with exercise, slow down while you're sleeping, or increase in preparation for a fight or flight situation. The SA node is supplied blood from the SA node artery, but can still be affected during myocardial infarction which can cause death to the SA node cells. This may cause a deficiency in the SA node's ability to act as a pacemaker, and can also lead to sick sinus syndrome. © sinoatrialnode.net

What is the substance that the body over-produces in an allergic reaction to pollen?

What Exactly Is an Allergy? Insect Allergies What is Happening During an Allergic Reaction? During an allergic process, the substance responsible for causing the allergy , or allergen, binds to allergic antibodies present on allergic cells in a person's body, including mast cells and basophils. These cells then release chemicals such as histamine and leukotrienes, resulting in allergic symptoms. How do Allergies Start? The allergic person can make allergic antibodies, or IgE, against a variety of allergens, including pollens , molds, animal danders, dust mites, foods, venoms and medications. This occurs through a process called sensitization, where a person’s immune system is exposed to enough of the allergen to make the body produce allergic antibodies to that substance. With later exposures, that same allergen binds to its corresponding IgE on allergic cells, and the body reacts with symptoms of allergies. Allergic symptoms can vary somewhat with the type of allergen and route of exposure (airborne pollen exposure may cause different symptoms than eating a food to which you are allergic). When and Why do People Develop Allergies? It is unknown why some people develop allergies and some don’t. Allergies seem to run in families, and in some cases, family members can share allergies to specific foods or medications. It appears that the allergic response was once meant to protect the body against parasitic infections, although now seems to be an abnormal response to non-infectious triggers. Allergies can occur at any time during our lives, but are more common to occur during childhood or young adulthood.

Which organ of the body secretes insulin?

How Insulin Works in the Body How Insulin Works in the Body Search the site By Elizabeth Woolley - Reviewed by a board-certified physician. Updated November 14, 2016 Insulin has a hand in several processes in your body: Not only does it assist with metabolizing carbohydrates and storing glucose for energy in cells, but it also helps utilize the fat, protein, and certain minerals you eat. Because this hormone is so important in helping your body use the foods you ingest, a problem with insulin can have widespread effects on all of your body's systems, tissues, and organs—either directly or indirectly. If you have type 2 diabetes, learning how insulin works can help you understand why so many other medical conditions are associated with diabetes, why certain lifestyle practices are beneficial, and how your body reacts to food. Where Insulin is Produced in the Body Insulin is a hormone made up of a small polypeptide protein that is secreted by the pancreas, which acts as both an endocrine and exocrine gland. Endocrine glands are the system of glands that secrete hormones to regulate body functions. Exocrine glands aid in digestion. The pancreas sits behind the stomach, nestled in the curve of the duodenum (the first part of the small intestine), and contains clusters of cells called islets of Langerhans. Islets are made up of beta cells, which produce and release insulin into the bloodstream. Insulin is Part of a Balancing Act Insulin affects carbohydrate, protein, and fat metabolism. Your body breaks these nutrients down into sugar molecules, amino acid molecules, and lipid molecules, respectively. The body can also store and reassemble these molecules into more complex forms. Insulin causes the storage of these nutrients, while another pancreatic hormone called glucagon releases them from storage. Insulin is involved in your body's careful balancing act to keep your blood sugar levels within a normal range. In simple terms: If your blood sugar is high: The pancreas releases insulin to help cells absorb glucose from the bloodstream to lower blood sugar levels. If your blood sugar is low: The pancreas releases glucagon to help the liver release stored glucose into the bloodstream to raise blood sugar levels. Blood sugar levels rise when most foods are consumed, but they rise more rapidly and drastically with carbohydrates. The digestive system releases glucose from foods and the glucose molecules are absorbed into the bloodstream. The rising glucose levels signal the pancreas to secrete insulin to clear out glucose from the bloodstream. Insulin binds with insulin receptors on cell surfaces and acts as a key to open up the cells to receive glucose. Insulin receptors are on almost all tissues, including muscle cells and fat cells. Insulin receptors have two main components—the exterior and interior portions. The exterior portion extends outside the cell and binds with insulin. When this happens, the interior part of the receptor sends out a signal inside the cell for glucose transporters to mobilize to the surface and receive glucose. As blood sugar and insulin levels decrease, the receptors empty and the glucose transporters go back into the cell. Insulin and Type 2 Diabetes In a perfect situation, glucose from carbohydrates gets cleared rapidly. However, when there is insulin resistance , this does not happen, and sustained high glucose levels become a problem. Insulin resistance can be due to a problem with the shape of the insulin (preventing receptor binding), not having enough insulin receptors, signaling problems, or glucose transporters not working properly. Whatever the specific cause, the function of insulin is impaired. Insulin resistance develops before type 2 diabetes is diagnosed. To make up for less effective insulin, the pancreas works overtime to increase insulin output. Eventually, some of the insulin works and blood sugar levels remain normal for a while. As insulin resistance worsens and the pancreas cannot keep up with the demand, glucose levels begin to rise and diabetes is diagnosed when levels get too

Which part of the gut absorbs water from thje food?

Absorption of Water and Electrolytes Glossary Absorption of Water and Electrolytes The small intestine must absorb massive quantities of water. A normal person or animal of similar size takes in roughly 1 to 2 liters of dietary fluid every day. On top of that, another 6 to 7 liters of fluid is received by the small intestine daily as secretions from salivary glands, stomach, pancreas, liver and the small intestine itself. By the time the ingesta enters the large intestine, approximately 80% of this fluid has been absorbed. Net movement of water across cell membranes always occurs by osmosis , and the fundamental concept needed to understand absorption in the small gut is that there is a tight coupling between water and solute absorption. Another way of saying this is that absorption of water is absolutely dependent on absorption of solutes, particularly sodium: Sodium is absorbed into the cell by several mechanisms, but chief among them is by cotransport with glucose and amino acids - this means that efficient sodium absorption is dependent on absorption of these organic solutes. Absorbed sodium is rapidly exported from the cell via sodium pumps - when a lot of sodium is entering the cell, a lot of sodium is pumped out of the cell, which establishes a high osmolarity in the small intercellular spaces between adjacent enterocytes. Water diffuses in response to the osmotic gradient established by sodium - in this case into the intercellular space. It seems that the bulk of the water absorption is transcellular, but some also diffuses through the tight junctions. Water, as well as sodium, then diffuses into capillary blood within the villus. Examine the animation above and consider the osmotic gradient between the lumen and the intercellular space (inside the villus). As sodium (green balls) is rapidly pumped out of the cell, it achieves very high concentration in the narrow space between enterocytes. The osmotic gradient is thus formed across apical cell membranes and their connecting junctional complexes. The arrow that appears denotes movement of water across the epithelium. Water is thus absorbed into the intercellular space by diffusion down an osmotic gradient. However, looking at the process as a whole, transport of water from lumen to blood is often against an osmotic gradient - this is important because it means that the intestine can absorb water into blood even when the osmolarity in the lumen is higher than osmolarity of blood. This ability is best explained by the " three compartment model " for absorption of water and, like many aspects of gut permeability, varies along the length of the gut. The proximal small intestine functions as a highly permeable mixing segment, and absorption of water is basically isotonic. That is, water is not absorbed until the ingesta has been diluted out to just above the osmolarity of blood. The ileum and especially the colon are able to absorb water against an osmotic gradient of several hundred milliosmols.

Where would you find the islets of Langerhans?

Definition of Islets of Langerhans Definition of Islets of Langerhans Causes of a Heart Attack Slideshow Islets of Langerhans: Known as the insulin -producing tissue, the islets of Langerhans do more than that. They are groups of specialized cells in the pancreas that make and secrete hormones. Named after the German pathologist Paul Langerhans (1847-1888), who discovered them in 1869, these cells sit in groups that Langerhans likened to little islands in the pancreas. There are five types of cells in an islet: alpha cells that make glucagon , which raises the level of glucose (sugar) in the blood; beta cells that make insulin; delta cells that make somatostatin which inhibits the release of numerous other hormones in the body; and PP cells and D1 cells, about which little is known. Degeneration of the insulin-producing beta cells is the main cause of type I (insulin-dependent) diabetes mellitus. Last Editorial Review: 5/13/2016

What is the colored muscle that responds involuntarily to light?

Pupil: Light, Perception & Life Science Activity | Exploratorium Teacher Institute Project None needed. To Do and Notice Place the magnifying glass on the surface of the mirror. Look into the center of the magnifying glass with one eye. If you wear contact lenses or glasses, you may either leave them on or remove them. Adjust your distance from the mirror until you see a sharply focused and enlarged image of your eye. You may need to adjust the position of the magnifier to get the clearest image of your eye. Notice the white of your eye, the colored disk of your iris, and your pupil, the black hole in the center of your iris. Shine a light into the pupil of one eye. If you are using a small mirror, hold the flashlight behind the mirror and shine the light around the edge of the mirror into your eye. If you are using a large mirror, bounce the flashlight beam off the mirror into your eye. Observe how your pupil changes size. Notice that it takes longer for your pupil to dilate than it does to contract. Notice also that the pupil sometimes overshoots its mark. You can see it shrink down too far, and then reopen slightly. Observe changes in the size of one pupil while you, or a partner, shine a light into and away from the other eye. In a dimly lit room, open and close one eye while observing the pupil of the other eye in the mirror. What's Going On? The pupil is an opening that lets light into your eye. Since most of the light entering your eye does not escape, your pupil appears black. In dim light, your pupil expands to allow more light to enter your eye. In bright light, it contracts. Your pupil can range in diameter from 1/16 inch (1.5 mm) to more than 1/3 inch (8 mm). Light detected by the retina of your eye is converted to nerve impulses that travel down the optic nerve. Some of these nerve impulses go from the optic nerve to the muscles that control the size of the pupil. More light creates more impulses, causing the muscles to close the pupil. Part of the optic nerve from one eye crosses over and couples to the muscles that control the pupil size of the other eye. That’s why the pupil of one eye can change when you shine the light into your other eye. In this experiment, the light reflecting from your eye passes through the magnifying lens twice—once on its way to the mirror and once on its way back. Therefore, the image of your eye is magnified twice by the magnifying glass. Going Further The size of your pupils actually reflects the state of your body and mind. Pupil size can change because you are fearful, angry, in pain, in love, or under the influence of drugs. Not only does the pupil react to emotional stimuli, it is itself an emotional stimulus. The size of a person’s pupils can give another person a strong impression of sympathy or hostility. The response of the pupil is an involuntary reflex. Like the knee-jerk reflex, the pupillary response is used to test the functions of people who might be ill or injured. You may have seen a doctor shine light into the eyes of a person with a suspected head injury—they are looking at the pupillary response. The pupil of your eye is also the source of the red eyes you sometimes see in flash photographs. When the bright light of a camera flash shines directly through the pupil, it can reflect off the choroid, which supplies red blood to the retina (the light-sensitive lining at the back of your eye), and bounce right back out through the pupil. If this happens, the person in the photograph will appear to have glowing red eyes. To avoid this, photographers move the flash away from the camera lens. With this arrangement, the light from the flash goes through the pupil at an angle, illuminating a part of the retina not captured by the camera lens. Many cameras are equipped with red-eye reduction features, such as a pre-flash that causes pupil constriction before the actual flash that illuminates the photo. Related Snacks

What is the name of the enzyme produced in the mouth?

Names of the Enzymes in the Mouth & Esophagus | The Classroom | Synonym Names of the Enzymes in the Mouth & Esophagus by Andrea Becker The enzymes in your saliva start the digestion process when you put food in your mouth. Related Articles How Does Temperature Affect Metabolism? You might think of the stomach or the intestines when you think of digestive enzymes, but the process of digestion starts the moment food enters your mouth. The mouth and esophagus themselves don’t produce any enzymes, but saliva, produced in the salivary glands and excreted into the mouth, contains several important enzymes. Saliva is mixed with food as you chew, acting as a lubricant and starting the digestion process. The enzymes in saliva start to break down nutrients and protect you from bacteria. Salivary Amylase One of the primary enzymes in saliva is amylase. Amylase starts to break down starches in the food you eat. Starches are long chains of sugars attached to each other, and amylase breaks the bonds along the chain to release maltose sugar molecules. To experience amylase in action, chew on a cracker for a minute and you will find that it starts to taste sweet. Amylase functions in a neutral to slightly basic environment, which is definitely not to be found in the acid bath that is your stomach. Lysozyme Secretion Lysozyme is secreted in your tears, the mucus in your nose and your saliva. Lysozyme isn’t there to digest your food, it is there to protect you from any harmful bacteria that came with it. Lysozyme breaks down the polysaccharides in the cell walls of many bacteria. Once the cell wall has been broken down, a bacterium dies, bursting like a water balloon. In scientific terms, cell death by popping is known as lysis, so the enzyme that accomplishes the task is called lysozyme. Lingual Lipase Lingual lipase is an enzyme that breaks down fats, specifically triacylglycerols. It is excreted as part of saliva, but it doesn’t finish its job until it gets to the stomach. The amount of lingual lipase in your saliva decreases as you get older, and gastric and pancreatic lipase lower down in your digestive system take over the job of digesting fats. Lingual lipase is very important for infants because it helps them digest the fats in milk, making digestion much easier for their immature systems. Salivary Kallikrein Kallikrein is the name for a group of proteases, enzymes that break down proteins, which are found throughout the body, including trace amounts in the saliva. The function of salivary kallikrein is not to digest the proteins you consume, however. Salivary kallikrein breaks down very specific proteins with a high molecular weight to produce bradykinin, a protein that helps blood vessels dilate. Changes to kallikrein enzymes have also been linked to certain cancers. References

The pituitary controls many hormones, but what controls the pituitary?

You & Your Hormones | Glands | Pituitary gland You & Your Hormones   Email article to a friend | Last updated: January 21, 2015 The pituitary gland is a small pea-sized gland that plays a major role in regulating vital body functions and general wellbeing. It is referred to as the body’s ‘master gland’ because it controls the activity of most other hormone-secreting glands. Computer artwork of a person's head showing the left hemisphere of the brain inside. The highlighted area (centre) shows the pituitary gland attached to the bottom of the hypothalamus at the base of the brain. Alternative names Hypophysis. Where is my pituitary gland? The pituitary gland is a pea-sized gland. It sits in the sella turcica (‘Turkish saddle’), a bony hollow in the base of the skull, underneath the brain and behind the bridge of the nose. Although the pituitary gland looks like one gland, it actually has two distinct parts, the anterior pituitary gland and the posterior pituitary gland. The gland is attached to the hypothalamus , the part of the brain that controls its activity. The anterior part of the pituitary gland consists of gland cells, which are connected to the brain by very short blood vessels. The posterior pituitary gland is actually part of the brain and it secretes hormones directly into the bloodstream under the command of the brain.  What does my pituitary gland do? The pituitary gland is called the ‘master gland’ as the hormones it produces control so many different processes in the body. It senses the body’s needs and sends signals to different organs and glands throughout the body to regulate their function and maintain an appropriate environment. It secretes a variety of hormones into the bloodstream which act as messengers to transmit information from the pituitary gland to distant cells, regulating their activity. For example, the pituitary gland produces prolactin , which acts on the breasts to induce milk production. The pituitary gland also secretes hormones that act on the adrenal glands , thyroid gland , ovaries and testes , which in turn produce other hormones. Through production of its hormones, the pituitary gland controls metabolism , growth, sexual maturation, reproduction, blood pressure and many other vital physical functions and processes. What hormones does my pituitary gland produce? The anterior pituitary gland produces the following hormones and releases them into the bloodstream: Adrenocorticotropic hormone , which stimulates the adrenal glands to secrete steroid hormones, principally cortisol   Thyroid stimulating hormone , which stimulates the thyroid gland to secrete thyroid hormones. There are also some hormones that are produced by the hypothalamus and then stored in the posterior pituitary gland prior to being released into the bloodstream. These are: Anti-diuretic hormone , which controls water balance and blood pressure. It is made by the hypothalamus but is stored in the posterior pituitary gland prior to being released into the bloodstream.   Oxytocin , which stimulates uterine contractions during labour and milk secretion during breastfeeding. It is made by the hypothalamus but is stored in the posterior pituitary gland prior to being released into the bloodstream. Each of these hormones is made by a separate type of cell within the pituitary gland, except for follicle stimulating hormone and luteinising hormone, which are made together by the same cell.  What could go wrong with my pituitary gland? The pituitary gland is an important gland in the body and the hormones it produces carry out varied tasks and regulate the function of many other organs. This means that the symptoms experienced when the pituitary gland stops working correctly can be varied depending on which hormone is affected.    Conditions that affect the pituitary gland directly can be divided into three main categories: Conditions that cause the pituitary gland to produce too much of one or more hormone(s). Examples include acromegaly , Cushing's disease and prolactinoma .   Conditions that cause the pituitary gland to p

What is the pigment that colors skin?

Hyperpigmentation and Hypopigmentation: Albinism, Vitiligo, and More Pigmentation is the coloring of a person's skin . When a person is healthy, his or her skin color will appear normal. In the case of illness or injury, the person's skin may change color, becoming darker (hyperpigmentation) or lighter (hypopigmentation). Hyperpigmentation and Skin Hyperpigmentation in skin is caused by an increase in melanin, the substance in the body that is responsible for color (pigment). Certain conditions, such as pregnancy or Addison's disease (decreased function of the adrenal gland), may cause a greater production of melanin and hyperpigmentation. Exposure to sunlight is a major cause of hyperpigmentaion, and will darken already hyperpigmented areas. Hyperpigmentation can also be caused by various drugs, including some antibiotics , antiarrhythmics, and antimalarial drugs. Melasma An example of hyperpigmentation is melasma (also known as chloasma). This condition is characterized by tan or brown patches, most commonly on the face. Melasma can occur in pregnant women and is often called the "mask of pregnancy;" however, men can also develop this condition. Melasma sometimes goes away after pregnancy. It can also be treated with certain prescription creams (such as hydroquinone ). If you have melasma, try to limit your exposure to daylight. Wear a broad-brimmed hat and use a sunscreen with an SPF of 30 or higher at all times, because sunlight will worsen your condition. Sunscreens containing the physical blockers zinc oxide or titanium dioxide are also helpful in blocking daylight’s UVA rays, which makes hyperpigmentation worse. Consult with your doctor before treating the condition yourself. Hypopigmentation and Skin Hypopigmentation in skin is the result of a reduction in melanin production. Examples of hypopigmentation include: Vitiligo : Vitiligo causes smooth, white patches on the skin. In some people, these patches can appear all over the body. It is an autoimmune disorder in which the pigment-producing cells are damaged. There is no cure for vitiligo, but there are several treatments, including cosmetic cover-ups, corticosteroid creams, or ultraviolet light treatments. Albinism : Albinism is a rare inherited disorder caused by the absence of an enzyme that produces melanin. This results in a complete lack of pigmentation in skin, hair , and eyes . Albinos have an abnormal gene that restricts the body from producing melanin. There is no cure for albinism. People with albinism should use a sunscreen at all times because they are much more likely to get sun damage and skin cancer . This disorder can occur in any race, but is most common among whites. Pigmentation loss as a result of skin damage: If you've had a skin infection, blisters , burns, or other trauma to your skin, you may have a loss of pigmentation in the affected area. The good news with this type of pigment loss is that it's frequently not permanent, but it may take a long time to re-pigment. Cosmetics can be used to cover the area, while the body regenerates the pigment. Continued

Which tissue secretes progesterone during the second half of the menstrual cycle?

You & Your Hormones | Hormones | Progesterone You & Your Hormones   Email article to a friend | Last updated: January 14, 2015 Progesterone is a hormone released by the corpus luteum in the ovary. It plays important roles in the menstrual cycle and in maintaining the early stages of pregnancy. It may also be involved in the growth of certain cancers. What is progesterone? Progesterone belongs to a group of steroid hormones called progestogens . It is mainly secreted by the corpus luteum in the ovary during the second half of the menstrual cycle.  It plays important roles in the menstrual cycle and in maintaining the early stages of pregnancy. During the menstrual cycle, when an egg is released from the ovary at ovulation (approximately day 14), the remnants of the ovarian follicle that enclosed the developing egg form a structure called the corpus luteum. This releases progesterone and, to a lesser extent, oestradiol . The progesterone prepares the body for pregnancy in the event that the released egg is fertilised. If the egg is not fertilised, the corpus luteum breaks down, the production of progesterone falls and a new menstrual cycle begins. If the egg is fertilised, progesterone stimulates the growth of blood vessels that supply the lining of the womb (endometrium) and stimulates glands in the endometrium to secrete nutrients that nourish the early embryo. Progesterone then prepares the tissue lining of the uterus to allow the fertilised egg to implant and helps to maintain the endometrium throughout pregnancy. During the early stages of pregnancy, progesterone is still produced by the corpus luteum and is essential for supporting the pregnancy and establishing the placenta . Once the placenta is established, it then takes over progesterone production at around week 12 of pregnancy. During pregnancy, progesterone plays an important role in the development of the foetus; stimulates the growth of maternal breast tissue; prevents lactation; and strengthens the pelvic wall muscles in preparation for labour . The level of progesterone in the body steadily rises throughout pregnancy until labour occurs and the baby is born. Although the corpus luteum in the ovaries is the major site of progesterone production in humans, progesterone is also produced in smaller quantities by the ovaries themselves, the adrenal glands and, during pregnancy, the placenta. How is progesterone controlled? The formation of the corpus luteum (which produces the majority of progesterone) is triggered by a surge in luteinising hormone production by the anterior pituitary gland . This normally occurs at approximately day 14 of the menstrual cycle and it stimulates the release of an egg from the ovary and the formation of the corpus luteum. The corpus luteum then releases progesterone which prepares the body for pregnancy. If the egg is not fertilised and no embryo is conceived, the corpus luteum breaks down and the production of progesterone decreases. As the lining of the womb is no longer maintained by progesterone from the corpus luteum, it breaks away and menstrual bleeding occurs, marking the start of a new menstrual cycle. However, if the ovulated egg is fertilised and gives rise to an embryo, the cells that surround this early embryo (which are destined to form the placenta) will secrete human chorionic gonadotrophin . This hormone has a very similar chemical structure to luteinising hormone. This means it can bind to and activate the same receptors as luteinising hormone, meaning that the corpus luteum does not break down and instead keeps producing progesterone until the placenta is established.  What happens if I have too much progesterone? There are no known serious medical consequences of having too much progesterone. Levels of progesterone do increase naturally in pregnancy as mentioned above. High levels of progesterone are associated with the condition congenital adrenal hyperplasia . However, the high progesterone levels are a consequence of and not a cause of this condition. Also, high levels of progesterone are associated with an

Which gland secretes the corticosteroids?

Adrenal Glands | Johns Hopkins Medicine Health Library Adrenal Glands: What You Need to Know Adrenal glands, also known as suprarenal glands, are small, triangular-shaped glands located on top of both kidneys. Adrenal glands produce hormones that help regulate your metabolism, immune system, blood pressure, response to stress and other essential functions. Adrenal glands are composed of two parts — the cortex and the medulla — which are each responsible for producing different hormones. When adrenal glands don’t produce enough hormones, this can lead to adrenal insufficiency (Addison’s disease). Adrenal glands may develop nodules that can be benign or malignant. These nodules may produce excessive amounts of certain hormones leading to various health issues. Anatomy of the Adrenal Glands An adrenal gland is made of two main parts: The adrenal cortex is the outer region and also the largest part of an adrenal gland. It is divided into three separate zones: zona glomerulosa, zona fasciculata and zona reticularis. Each zone is responsible for producing specific hormones. The adrenal medulla is located inside the adrenal cortex in the center of an adrenal gland. It produces several “stress hormones,” including adrenaline. The adrenal cortex and adrenal medulla are enveloped in an adipose capsule that forms a protective layer around an adrenal gland. Hormones of the Adrenal Glands The role of the adrenal glands in your body is to release certain hormones directly into the bloodstream. Many of these hormones have to do with how the body responds to stress, and some are vital to existence. Both parts of the adrenal glands — the adrenal cortex and the adrenal medulla — perform distinct and separate functions. Each zone of the adrenal cortex secretes a specific hormone. The key hormones produced by the adrenal cortex include: Cortisol Cortisol is a glucocorticoid hormone produced by the zona fasciculata that plays several important roles in the body. It helps control the body’s use of fats, proteins and carbohydrates; suppresses inflammation; regulates blood pressure; increases blood sugar; and can also decrease bone formation. This hormone also controls the sleep/wake cycle. It is released during times of stress to help your body get an energy boost and better handle an emergency situation. How Adrenal Glands Work to Produce Cortisol Adrenal glands produce hormones in response to signals from the hypothalamus and the pituitary gland in the brain. For example, for the adrenal gland to produce cortisol: The hypothalamus produces corticotropin-releasing hormone (CRH) that stimulates the pituitary gland to secrete adrenocorticotropin hormone (ACTH). The ACTH then stimulates the adrenal glands to make and release cortisol hormones into the blood. Normally, both the hypothalamus and the pituitary gland can sense whether the blood has the right amount of cortisol in it. If there is too much or too little cortisol, these glands respectively change the amount of CRH and ACTH that gets released. Excess cortisol production can occur from nodules in the adrenal gland or excess production of ACTH from a tumor in the pituitary gland or other source. Aldosterone This mineralocorticoid hormone produced by the zona glomerulosa plays a central role in regulating blood pressure and certain electrolytes (sodium and potassium). Aldosterone sends signals to the kidneys, resulting in the kidneys absorbing more sodium into the bloodstream and releasing potassium into the urine. This means that aldosterone also helps regulate the blood pH by controlling the levels of electrolytes in the blood. DHEA and Androgenic Steroids These hormones produced by the zona reticularis are weak male hormones. They are precursor hormones that are converted in the ovaries into female hormones (estrogens) and in the testes into male hormones (androgens). However, estrogens and androgens are produced in much larger amounts by the ovaries and testes. Epinephrine (Adrenaline) and Norepinephrine (Noradrenaline) The adrenal medulla, the inner part of an adrenal gland, controls

What are the natural pain-killing substances produced in the brain and pituitary gland?

Endorphins | definition of endorphins by Medical dictionary Endorphins | definition of endorphins by Medical dictionary http://medical-dictionary.thefreedictionary.com/endorphins Related to endorphins: dopamine , serotonin en·dor·phins (en-dōr'finz, en'dōr-finz), Opioid peptides originally isolated from the brain but now found in many parts of the body; in the nervous system, endorphins bind to the same receptors that bind exogenous opiates. A variety of endorphins (for example, α, β, and γ) that vary not only in their physical and chemical properties but also in physiologic action have been isolated. [fr. endogenous morphine] endorphins A number of morphine-like peptide substances naturally produced in the body and for which morphine receptors exist in the brain. Many of these active substances have been found, all with the same opioid core of five amino acids. They are neurotransmitters and have a wide range of functions. They help to regulate heart action, general hormone function, the mechanisms of shock from blood loss and the perception of pain, and are probably involved in controlling mood, emotion and motivation. They are thought to be produced under various circumstances in which acute relief of pain or mental distress is required. At least some of the endorphins are produced by the PITUITARY gland as part of the precursor of the ACTH molecule. Endorphins are fragments cleaved from the beta-lipotropin component of proopiomelanocortin ( POMC ). The term derives from the phrase ‘endogenous morphines’. Endorphins Pain-killing substances produced in the human body and released by stress or trauma. Some researchers think that people who mutilate themselves are trying to trigger the release of endorphins. Mentioned in: Methadone , Pet Therapy , Self-Mutilation , Stress Reduction endorphins group of opioid peptides made in nerve cells in the brain and released from their axons as neurotransmitters or neurohormones, which bind to and activate opioid receptors of other cells (where opioid drugs also act). The first to be identified in brain tissue (1970s) were named enkephalins; many more were later identified. They are released in strenuous exercise and in stressful or painful situations. Subgroups have varied and widespread actions, diminishing the sensation of pain, inducing euphoria (e.g. 'runner's high') and interacting with the immune system. endorphins naturally occurring opioids liberated within brain, spinal cord and peripheral tissues during exercise; interact with tissue opiate receptors, inducing pain reduction, euphoria and general well-being endorphins, n.pl polypeptides produced in the body that bind the neuroreceptors in brain and act on the central and peripheral nervous system to alleviate pain. en·dor·phins (en-dōr'finz)

What hormone was discovered by John Jacob Abel?

The Sucrose Molecule The Epinephrine Molecule using Jmol -- For 3D Structures Epinephrine or adrenaline (European Pharmacopoeia and BAN) , sometimes spelled "epinephrin" or "adrenalin" respectively, is a hormone when carried in the blood and a neurotransmitter when it is released across a neuronal synapse. It is a catecholamine, a sympathomimetic monoamine derived from the amino acids phenylalanine and tyrosine. The Latin roots ad-+renes and the Greek roots epi-+nephros both literally mean "on/to the kidney" (referring to the adrenal gland, which sits atop the kidneys and secretes epinephrine). Epinephrine is sometimes shortened to epi or to EP in medical jargon. History In May 1886, William Bates reported the discovery of a substance produced by the adrenal gland in the New York Medical Journal. Epinephrine was isolated and identified in 1895 by Napoleon Cybulski, a Polish physiologist. The discovery was repeated in 1897 by John Jacob Abel.[1]. Jokichi Takamine, a Japanese chemist, independently discovered the same hormone in 1900.[2][3]In 1901 he isolated and purified the hormone adrenaline from cow glands.It was first artificially synthesized in 1904 by Friedrich Stolz. Triggers Epinephrine is a "fight or flight" hormone, and plays a central role in the short-term stress reaction. It is released from the adrenal glands when danger threatens or in an emergency. Such triggers may be threatening, exciting, or environmental stressor conditions such as high noise levels or bright light (see Fight-or-flight response). An example of noise-induced trigger of epinephrine release is tinnitus. The fight-or-flight response caused by tinnitus is a contributor to physical stress seen in tinnitus-patients,[4] exacerbating the case. Actions in the body When secreted into the bloodstream, it rapidly prepares the body for action in emergency situations. The hormone boosts the supply of oxygen and glucose to the brain and muscles, while suppressing other non-emergency bodily processes (digestion in particular). It increases heart rate and stroke volume, dilates the pupils, and constricts arterioles in the skin and gut while dilating arterioles in skeletal muscles. It elevates the blood sugar level by increasing catalysis of glycogen to glucose in the liver, and at the same time begins the breakdown of lipids in fat cells. Like some other stress hormones, epinephrine has a suppressive effect on the immune system.[5] Although epinephrine does not have any psychoactive effects, stress or arousal also releases norepinephrine in the brain. Norepinephrine has similar actions in the body, but is also psychoactive. The type of action in various cell types depends on their expression of adrenergic receptors. Adrenergic receptors Epinephrine's actions are mediated through adrenergic receptors: It binds to α1 receptors of liver cells, which activate inositol-phospholipid signaling pathway, signaling the phosphorylation of glycogen synthase and glycogen phosphorylase (inactivating and activating them, respectively), leading to breakdown of glycogen (glycogenolysis) so as to release glucose to the bloodstream. Epinephrine also activates β-adrenergic receptors of the liver and muscle cells, thereby activating the adenylate cyclase signaling pathway, which will in turn increa

What is the substance produced by hard exercise and oxygen debt, causing stiffness in the muscles?

Oxygen Debt & Recovery | Energy Systems | Anatomy & Physiology Oxygen Debt & Recovery Oxygen Debt & Recovery What is it all about then? When you have a short intense burst of exercise such as sprinting you generate energy for this anaerobically or without oxygen. When you stop exercising you are still breathing heavily. This is your body taking in extra oxygen to 'repay' the oxygen debt. Well, that is the simple solution but there is a little more to it if you want to look a bit deeper. True, your body has worked anaerobically and will have produced energy without some of the oxygen it would normally have used performing low intensity exercise such as slow steady running. The difference between the oxygen the body required and what it actually managed to take in during the sudden sprint is called oxygen deficit. When you stop sprinting and start to recover you will actually need more oxygen to recover than your body would have liked to use had enough been available. This is called Excess Post Exercise Oxygen Consumption. So why does it take more oxygen to recover then? You needed to replace the oxygen the body needed but couldnt get (oxygen deficit). Breathing rate and heart rate are elevated (to remove CO2) and this needs more oxygen. Body temperature and metabolic rate is increased and this needs more oxygen. Adrenaline and Noradrenaline are increased which increases oxygen consumption.   So after exercise there are other factors causing an increase in oxygen needs as well as repaying the lack of oxygen during exercise. The chart below is often seen and shows how the amount of oxygen used by the body changes over time. At the beginning the body works anaerobically leaving an oxygen deficit. Over time the oxygen consumption levels out to a steady state. After exercise the oxygen is pain back (oxygen debt). Notice the area of oxygen debt is greater than the area of oxygen deficit for the reasons stated above. What has Lactic Acid got to do with it? Lactic acid is a by product of exercising without using oxygen (anaerobially). It is essential this is removed but it is not necessarily a waste product. It is recycled into other useful chemicals: During prolonged intensive exercise (e.g. 800m race) the heart may get half its energy from lactic acid. It is converted back to pyruvic acid and used as energy by the heart and other muscles. It is thought that 70% of lactic acid produced is oxidised, 20% is converted to glucose (energy) in the liver. 10% is converted to protein. How long does it take to remove lactic acid? About 1 hour if cooling down with gentle exercise. It can take 2 hours or more if you dont warm down with gentle exercise. More Anatomy & Physiology

Where would you find the carotid arteries?

An Overview of Carotid Artery Disease Sedentary lifestyle Family history of atherosclerosis, either coronary artery disease or carotid artery disease Men younger than age 75 have a greater risk than women in the same age group. Women have a greater risk than men older than age 75. People who have coronary artery disease have an increased risk of developing carotid artery disease. Typically, the carotid arteries become diseased a few years later than the coronary arteries. Continued What Are the Symptoms of Carotid Artery Disease? You may not have any symptoms of carotid artery disease. Plaque builds up in the carotid arteries over time with no warning signs until you have a transient ischemic attack (TIA) or a stroke. Signs of a stroke may include: Sudden loss of vision , blurred vision , or difficulty in seeing out of one or both eyes Weakness , tingling, or numbness on one side of the face, one side of the body, or in one arm or leg Sudden difficulty in walking, loss of balance, lack of coordination Sudden dizziness and/or confusion   How Is Carotid Artery Disease Diagnosed? There are often no symptoms of carotid artery disease until you have a TIA or stroke. That’s why it’s important to see your doctor regularly for physical exams. Your doctor may listen to the arteries in your neck with a stethoscope. If an abnormal sound, called a bruit, is heard over an artery, it may reflect turbulent blood flow. That could indicate carotid artery disease. Listening for a bruit in the neck is a simple, safe, and inexpensive way to screen for stenosis (narrowing) of the carotid artery, although it may not detect all blockages. Some experts believe that bruits may be better predictors of atherosclerotic disease rather than risk of stroke. Be sure to let your doctor know if you have had any symptoms, such as those listed above. Continued Your doctor may also use a test to diagnose carotid artery disease. Possible tests include the following: Carotid ultrasound (standard or Doppler). This noninvasive, painless screening test uses high-frequency sound waves to view the carotid arteries. It looks for plaques and blood clots and determines whether the arteries are narrowed or blocked. A Doppler ultrasound shows the movement of blood through the blood vessels. Ultrasound imaging does not use X-rays. Magnetic resonance angiography (MRA). This imaging technique uses a powerful magnet to gather accurate information about the brain and arteries. Then a computer uses this information to generate high-resolution images. An MRA can often detect even small strokes in the brain. Computerized tomography angiography (CTA). More detailed than an X-ray, a CT uses X-rays and computer technology to produce cross-sectional images of the carotid arteries. Images of the brain can be collected as well. With this imaging test, the scan may reveal areas of damage on the brain. The CT scan uses a low level of radiation . Cerebral angiography ( carotid angiogram ). This procedure is considered the gold standard for imaging the carotid arteries. It is an invasive procedure that lets a doctor see blood flow through the carotid arteries in real time. Cerebral angiography allows the doctor to see narrowing or blockages on a live X-ray screen as contrast dye is injected in the carotid arteries. This procedure provides the best information. It does carry a small risk of serious complications.   Continued Which Drugs Can Reduce the Risk of Stroke? Your doctor may recommend antiplatelet medications such as aspirin and clopidogrel (Plavix) to decrease the risk of stroke caused by blood clots. Your doctor may also prescribe medications to lower cholesterol and blood pressure . In some cases, warfarin ( Coumadin ), a blood thinner , may be prescribed.   What Medical Procedures Treat Carotid Artery Disease? If there is severe narrowing or blockage in the carotid artery, a procedure can be done to open the artery. This will increase blood flow to the brain to prevent future stroke. Your doctor may suggest either of the following procedures: Carotid endarterectomy (CEA). Thi

Which protein forms hair and nails?

Protein is important for beautiful skin, hair and nails - Nutrition Express Articles Protein is important for beautiful skin, hair and nails Learn why protein plays such a major role in your overall health by Judy Lindberg McFarland When you look in the mirror, what do you see? Do you see soft, supple, radiant, glowing, blemish-free skin? Or do you see age spots and new wrinkles? The skin is the first "aging" sign we tend to see in ourselves. We all want to find ways to keep our skin beautiful, soft, and, we hope, wrinkle free. We will each get some wrinkles, but nobody wants them prematurely! My mother, Gladys Lindberg, had the most beautiful skin for her age of any woman I have ever seen. She far surpassed the "beauty experts" and "movie stars" in her beauty and grace. At age 85 she had a clear, peachy complexion and was virtually wrinkle free! She had no patchy "age" spots or blemished skin. She never smoked and avoided the sun whenever possible. This was natural beauty. Mother started her quest for health when she was 43 years old. She said her skin was blotchy and never radiant, but her program drastically changed the quality of her skin. Important advice for skin health A woman recently came into our store looking for a "magic formula" for her deeply wrinkled skin. She was only in her mid-40s, but said her skin had changed drastically over the past months. Being quite disturbed about the situation, she came to me wanting "that miracle cream." I talked to her for a few minutes and discovered that she had been on a severe reducing diet for several months. She had followed a diet low in protein, and over the course of those months had lost her skin tone. It had started to sag and wrinkle way beyond what would be normal for her chronological age. Most women want to be slim, but if you saw her, I'm sure you would agree, "not at that price!" Here are some things I told her that are important for healthy skin regardless of whether you're trying to lose weight or not. Collagen - the skin's "cement" Elastic skin is a sign that a person has ample collagen, the strong cement-like material that binds together the cells of your body. Collagen is a structural tissue and it is replaced very slowly. It is made of fibrous protein. In fact, collagen comprises 30 percent of the total body protein. Its strong white fibers, stronger than steel wire of the same size, and yellow elastic networks, called elastin, form the connective tissue that holds our body together. Collagen strengthens the skin, blood vessels, bones, and teeth. It is the intracellular cement that holds together the cells in various organs and tissues. Collagen is one of the most valuable proteins in the human body. A person who has been sick, or who has been on an extremely low-protein diet, very often sees the muscles in his or her arms and legs begin to sag, which is a sign that they have probably lost collagen. Start with protein The building blocks of protein are amino acids. When protein is eaten, your digestive processes break it down into amino acids, which pass into the blood and are carried throughout the body. Your cells can then select the amino acids they need for the construction of new body tissue, antibodies, hormones, enzymes, and blood cells. There are 22 different amino acids, each of which has its own characteristics, and are like the letters of the alphabet. The eight essential amino acids are like the vowels. Just as you cannot make words without vowels, so you cannot build proteins without these essential amino acids. Protein is not one substance, but literally tens of thousands of different substances. The essential amino acids must be consumed in the diet because the body does not make them. The complete proteins that contain the eight essential amino acids come from meat, poultry, fish, eggs, milk -- all dairy, cheese and soy. They are basically anything that comes from the animal. Nuts and legumes (peas and beans) contain some but not all of the essential amino acids; these are known as incomplete proteins. In various combinations, all of the

Which gas released by car exhausts, stops the blood hemoglobin from working correctly?

What you need to know about carbon monoxide What you need to know about the leading cause of poisoning deaths in America Carbon Monoxide The following text is from the booklet What you need to know about the leading cause of poisoning deaths in America: Carbon monoxide (1996), prepared as a public service by First Alert in cooperation with the Cooperative State Research, Education, and Extension Service (CSREES) of the U.S. Department of Agriculture. If you have questions about carbon monoxide, contact your local gas utility, a qualified heating contractor, or the Extension Services office listed in the white pages of your phone book. What is carbon monoxide and who is at risk? Carbon monoxide (CO) is a colorless, odorless deadly gas. Because you can't see, taste, or smell it, carbon monoxide can kill you before you know it's there. Everyone is at risk for carbon monoxide poisoning. Experts believe, however, that individuals with greater oxygen requirements such as unborn babies, infants, children, senior citizens, and people with coronary or respiratory problems are at greater risk.   Why is carbon monoxide so dangerous? The great danger of carbon monoxide is its attraction to hemoglobin in the bloodstream. When breathed in, carbon monoxide replaces the oxygen which cells need to function. When CO is present in the air, it rapidly accumulates in the blood, causing symptoms similar to the flu, such as headaches, fatigue, nausea, dizzy spells, confusion, and irritability. As levels increase, vomiting, loss of consciousness, and eventually brain damage or death can result.   Where does carbon monoxide come from? Carbon monoxide is a by-product of combustion, present whenever fuel is burned. It is produced by common home appliances, such as gas or oil furnaces, gas refrigerators, gas clothes dryers, gas ranges, gas water heaters or space heaters, fireplaces, charcoal grills, and wood burning stoves. Fumes from automobiles and gas-powered lawn mowers also contain carbon monoxide and can enter a home through walls or doorways if an engine is left running in an attached garage. All of these sources can contribute to a CO problem in the home. If a home is vented properly and is free from appliance malfunctions, air pressure fluctuations or airway blockages, carbon monoxide will most likely be safely vented to the outside. But in today's "energy efficient" homes this is frequently not the case. Tightly constructed/sealed homes can trap CO-polluted air in a home year-round. Furnace heat exchangers can crack, vents can become blocked, inadequate air supply for combustion appliances can cause conditions known as backdrafting or reverse stacking, which force contaminated air back into the home. Exhaust fans on range hoods, clothes dryers and bathroom fans can also pull combustion products into the home.   How can I protect myself and my family from carbon monoxide poisoning? The Consumer Product Safety Commission (CPSC) recommends installing at least one carbon monoxide detector per household, near the sleeping area. Additional detectors on every level of a home and in every bedroom provide extra protection. Choose an Underwriters Laboratories Inc. (UL) listed detector that sounds an audible alarm. You can choose a model that is wired to your home's electrical system, a model which plugs into a standard electrical outlet, or a battery-operated model. Battery-operated carbon monoxide detectors continue to protect even in the event of a power outage. Hardwired AC models, although more costly and difficult to install, reduce the expense of battery replacement but do not offer protection during power outages. Hardwired AC models with battery back-up offer double protection. Gas appliances should be serviced yearly by a qualified service technician. Stove burners should be cleaned and adjusted to minimize the amount of carbon monoxide produced. Before making changes to a house that might affect the ventilation of fuel-burning appliances, contact your heating contractor. When replacing heating appliances, purchase appliances designed to r

What device is added to a car's exhaust system to reduce pollution?

Fuel + Air => Hydrocarbons + Nitrogen Oxides + Carbon Dioxide + Carbon Monoxide + Sulphur Dioxide+ water Hydrocarbon emissions are fragments of fuel molecules, only partially burned. See Toxicity Hydrocarbons in exhaust. Hydrocarbons react in the presence of nitrogen oxides and sunlight to form ground-level ozone, a major component of smog. Ozone irritates the eyes, nose, throat and damages the lungs. A number of exhaust hydrocarbons are also toxic, some with the potential to cause cancer. Nitrogen Oxides Under high pressure and temperature conditions in an engine, nitrogen and oxygen atoms react to form nitrogen oxides. Nitrogen dioxide, NO2, is a brownish toxic gas, an important air pollutant. The air of cities with high levels of car ownership has a distinctly brown tinge. NO2 combines with water in the air to form nitric acid - acid rain. A complex chemistry involves NO2 combining with hydrocarbons to form the photochemical smog that poisons city dwellers. Sunlight converts unburned hydrocarbons to more reactive molecules such as aldehydes and ketones which generate peroxyacyl radicals that react with NO2 forming peroxyacyl nitrates(PANs). Catalytic converters in car exhaust systems reduce air pollution in the best case by breaking down NO2 and N20 to nitrogen (N2) and oxygen(O2). Nitrous oxide (N2O) also known as "laughing gas" has medical uses, but is a pollutant in the air. N2O, for example gives rise to nitric oxide (NO) which reacts with  and depletes ozone. N2O is a combustion product but also originates from forest fires, lightning storms nitrogen-based fertilizers and manure from farm animals. According to the US EPA industrial sources make up only about 20% of all anthropogenic sources of N2O, including the burning of fossil fuel in internal combustion engines. Indoor gas burning appliances generate N2O.  It is also a major greenhouse gas and air pollutant with about 300 times more global-warming potential than carbon dioxide. Carbon Monoxide Carbon monoxide (CO) is a colorless, odorless, poisonous gas, a product of incomplete burning of hydrocarbon-based fuels. Carbon monoxide consists of a single carbon atom and a single oxygen atom linked together (CO), the product of incomplete combustion of fuel. Most CO is produced when air-to-fuel ratios are too low in the engine during vehicle starting, when cars are not tuned properly, and at higher altitudes, where thin air reduces the amount of oxygen available for combustion. Two-thirds of the carbon monoxide emissions come from transportation sources, with the largest contribution coming from cars. In urban areas, the passenger vehicle contribution to carbon monoxide pollution can exceed 90%.Read more about Carbon Monoxide Carbon Dioxide U.S. Environmental Protection Agency (EPA) originally viewed carbon dioxide as a product of "perfect" combustion, but now views CO2 as a pollution concern. Carbon dioxide is a greenhouse gas that traps the earth's heat and contributes to Climate Change Particle Pollution and Human Disease The U.S. Environmental Protection Agency (EPA) defines fine-particle air pollution, PM10, particulate matter 10 micrometers or less in diameter. Suspended particles in the air create aerosols that are important to the behavior of whole atmosphere and play a role in determining human disease. Natural sources of atmospheric particles are volcanoes, dust storms, spontaneous forest fires, tornadoes and hurricanes. Clouds are a product of aerosols that seed the formation of water droplets. Human air pollution now dominates aerosol production over cities with negative health effects. Thick aerosols are obvious as haze and contain a complex system of particles with adherent toxic gases such as sulphur dioxide. Air pollution is associated with increased hospital admissions for cardiovascular diseases with increases in acute morbidity and mortality. D'Ippoliti et al studied 6531 patients in Rome who were hospitalized for acute myocardial infarction from January 1995 to June 1997. Air pollution data were

Which Australian mammal lays eggs?

Why Odd Egg-Laying Mammals Still Exist Why Odd Egg-Laying Mammals Still Exist By Charles Q. Choi, Live Science Contributor | September 21, 2009 11:06am ET MORE The platypus, found only in Australia is one of the five mammal species of that lay eggs instead of giving birth to live young. The other egg-laying mammals are four species of echidna. Credit: Gerry Pearce, australian-wildlife.com. The reason that odd, egg-laying mammals still exist today may be because their ancestors took to the water, scientists now suggest. The egg-laying mammals — the monotremes, including the platypus and spiny anteaters — are eccentric relatives to the rest of mammals, which bear live young. In addition to laying eggs, other quirks make them seem more like reptiles than our kin. They have a reptilian gait with legs on the sides rather than underneath the body, for instance, and a single duct for urine, feces and sex instead of multiple openings. These oddballs are often considered primitive "living fossils" that shed light on what our distant ancestors might have looked like. Australian invasion Long ago, monotremes and their close relatives were the dominant mammals in the whole of Australia. Now only two kinds of monotremes are left on the planet — the duck-billed platypuses and the four species of echidnas, or spiny anteaters. Like all mammals, they possess hair, milk, sweat glands, three middle ear bones and a brain region known as the neocortex. The monotremes were almost totally swept aside when their pouch-bearing marsupial cousins — modern examples of which include the kangaroos — invaded Australia 71 million to 54 million years ago. Marsupials appear to have a number of advantages over monotremes — their bodies seem more efficient at locomotion, and the fact that they give birth to live offspring could provide better care of young. Moreover, before the marsupials reached Australia, they had migrated from Asia to the Americas to Antarctica. The struggle marsupials presumably had with all the animals on these continents during this journey might have primed them for competition, "while the Australian mammals [including monotremes] that went extinct upon the arrival of marsupials had for the most part been isolated in Australia for a very long time," explained researcher Matthew Phillips, an evolutionary biologist at the Australian National University in Canberra. All these strengths help explain why marsupials triumphed in Australia. The mystery then is why any monotremes survived. Swim for it! Now Phillips and his colleagues suggest that platypuses and echidnas lived on because their ancestors sought refuge where marsupials could not follow — the water. Platypuses are amphibious creatures, while echidnas — the anteaters — are terrestrial. However, new genetic evidence and comparisons with fossil monotremes suggests that echidnas only diverged from platypuses 19 to 48 million years ago. This means echidnas recently had semi-aquatic predecessors and only later recolonized the land. A number of aspects of echidna biology are consistent with an amphibious platypus-like ancestor — a streamlined body, rearward-jutting hind limbs that could act as rudders, and the contours of a duck-like bill during embryonic development. "Platypus-like fossils are known from at least 61 million years ago. It was thought that the much shorter fossil record for echidnas, from about 13 million years ago, was just due to the patchy nature of the fossil record," Phillips said. Their new findings suggest "the lack of early echidna fossils was in fact because they simply had not evolved yet." The researchers conjecture that marsupials could not afford a substantial invasion of aquatic environments because when they are born, they need to suckle milk constantly for weeks; newborn marsupials could drown if their mothers ever had to venture into the water. Evidence fits These findings remove an apparent contradiction between fossil data and DNA evidence, said Zhe-Xi Luo, curator of vertebrate paleontology at the Carnegie Museum of Natural History in Pittsburgh. Ev

What is the term for something that will break down naturally?

Terms to Know Biodegradable Definition A “biodegradable” product has the ability to break down, safely and relatively quickly, by biological means, into the raw materials of nature and disappear into the environment.  These products can be solids biodegrading into the soil (which we also refer to as compostable), or liquids biodegrading into water.  Biodegradable plastic is intended to break up when exposed to microorganisms (a natural ingredient such as cornstarch or vegetable oil is added to achieve this result). Sustainable disposal of any product requires that its wastes return to the earth and are able to biodegrade.  Nature biodegrades everything it makes back into basic building blocks, so that new living things can be made from the old.  Every resource made by nature returns to nature - plants and animals biodegrade, even raw crude oil will degrade when exposed to water, air and the necessary salts.  Nature has perfected this system - we just need to learn how to participate in it. By the time many resources are turned into products, however, they have been altered by industry in such a way that they are unrecognizable to the microorganisms and enzymes that return natural materials to their basic building blocks.  Crude oil, for example, will biodegrade in its natural state, but once it is turned into plastic, it becomes an unsustainable pollution problem.  Instead of returning to the cycle of life, these products simply pollute and litter our land, air and water. Of all the environmental buzzwords “biodegradable” has perhaps been the most misused and the most difficult to understand.  Because in the past there have been no guidelines or regulations, many products have called themselves biodegradable without any real justification.  Unfortunately, the word biodegradable has frequently been applied to products that generally aren’t (such as detergents or plastics) and almost never used for products that really are (such as soap or paper). A leaf is a perfect example of a biodegradable product -- it is made in the spring, used by the plant for photosynthesis in the summer, drops to the ground in autumn and assimilated into the soil to nourish the plant for the next season.  The basic concept seems straightforward enough, however, there are several factors to consider in determining the biodegradability of a product or material. The first is the question of the inherent biodegradability of the material.  Any material that comes from nature will return to nature as long as it is still in a relatively natural form.  Therefore, any plant-based, animal-based or natural mineral-based product has the capability to biodegrade, but products made from man-made petrochemical compounds generally do not.  When a manmade compound is formulated in a laboratory, combinations of elements are made that do not exist in nature and there are no corresponding microorganisms to break them down. The next issue is how long it takes for the material to actually break down.  In nature, different materials biodegrade at different rates.  A leaf takes approximately a year to become part of the forest floor.  An iron shovel, on the other hand, can take years to rust away to nothing and a large tree can take decades to completely break down.  Common sense tells us that any material will ultimately biodegrade, even if it takes centuries. So what is the proper rate for a material to be biodegradable?  It really depends on the material itself.  The leaf example suggests that the proper rate is that which is appropriate to the ecosystem. A liquid going into a waterway should biodegrade fairly quickly, whereas there’s no harm done if it takes a while for a newspaper to break down.  Plastics, on the other hand, will not biodegrade in anyone’s lifetime and certainly will never break back down into the petroleum from which it is made. And then there is the question of what

Which is the most common gas in the atmosphere?

Earth's Atmosphere | UCAR Center for Science Education Earth's Atmosphere The layered structure of Earth's atmosphere is visible in this sunset view from the International Space Station. Credit: Image Science & Analysis Laboratory, NASA Johnson Space Center Earth's atmosphere is a mixture of gases that surrounds our home planet. Besides providing us with something to breathe, the atmosphere helps make life on Earth possible in several ways. It shields us from most of the harmful ultraviolet (UV) radiation coming from the Sun, warms the surface of our planet by about 33° C (59° F) via the greenhouse effect, and largely prevents extreme differences between daytime and nighttime temperatures. The atmosphere is a mixture of many different gases. Nitrogen and oxygen are by far the most common; dry air is composed of about 78% nitrogen (N2) and about 21% oxygen (O2). Argon, carbon dioxide (CO2) , and many other gases are also present in much lower amounts; each makes up less than 1% of the atmosphere's mixture of gases. The atmosphere also includes water vapor. The amount of water vapor present varies a lot, but on average is around 1%. There are also many small particles - solids and liquids - "floating" in the atmosphere. These particles, which scientists call "aerosols", include dust, spores and pollen, salt from sea spray, volcanic ash, smoke, and more. The atmosphere grows thinner (less dense and lower in pressure) as one moves upward from Earth's surface. It gradually gives way to the vacuum of outer space. There is no precise "top" of the atmosphere. Air becomes so thin at altitudes between 100 and 120 km (62-75 miles) up that for many purposes that range of heights can be considered the boundary between the atmosphere and space. However, there are very thin but measurable traces of atmospheric gases hundreds of kilometers/miles above Earth's surface. There are several different regions or layers in the atmosphere. Each has characteristic temperatures, pressures, and phenomena. We live in the troposphere , the lowest layer, where most clouds are found and almost all weather occurs. Some jet aircraft fly in the next higher layer, the stratosphere , which contains the jet streams and the ozone layer. Higher still are the mesosphere , thermosphere and exosphere . © 2011 UCAR

Which fuel is formed by the fossilization of plants?

DOE - Fossil Energy: How Fossil Fuels Were Formed You are here:  Educational Activities  >  Energy Lessons  >  Coal-Introduction  > Fossil Fuel Formation How Fossil Fuels were Formed Contrary to what many people believe, fossil fuels are not the remains of dead dinosaurs. In fact, most of the fossil fuels we find today were formed millions of years before the first dinosaurs.   Formation of Coal   Fossil fuels were formed from plants and animals that lived 300 million years ago in primordial swamps and oceans (top). Over time the plants and animals died and decomposed under tons of rock and ancient seas (middle). Eventually, many of the seas receded and left dry land with fossil fuels like coal buried underneath it (bottom). Ten feet of prehistoric plant debris was needed to make one foot of coal.   Fossil fuels, however, were once alive! They were formed from prehistoric plants and animals that lived hundreds of millions of years ago. Think about what the Earth must have looked like 300 million years or so ago. The land masses we live on today were just forming. There were swamps and bogs everywhere. The climate was warmer. Ancient trees and plants grew everywhere. Strange looking animals walked on the land, and just as weird looking fish swam in the rivers and seas. Tiny one-celled organisms called protoplankton floated in the ocean. When these ancient living things died, they decomposed and became buried under layers and layers of mud, rock, and sand. Eventually, hundreds and sometimes thousands of feet of earth covered them. In some areas, the decomposing materials were covered by ancient seas, then the seas dried up and receded. During the millions of years that passed, the dead plants and animals slowly decomposed into organic materials and formed fossil fuels. Different types of fossil fuels were formed depending on what combination of animal and plant debris was present, how long the material was buried, and what conditions of temperature and pressure existed when they were decomposing. For example, oil and natural gas were created from organisms that lived in the water and were buried under ocean or river sediments. Long after the great prehistoric seas and rivers vanished, heat, pressure and bacteria combined to compress and "cook" the organic material under layers of silt. In most areas, a thick liquid called oil formed first, but in deeper, hot regions underground, the cooking process continued until natural gas was formed. Over time, some of this oil and natural gas began working its way upward through the earth's crust until they ran into rock formations called "caprocks" that are dense enough to prevent them from seeping to the surface. It is from under these caprocks that most oil and natural gas is produced today. The same types of forces also created coal, but there are a few differences. Coal formed from the dead remains of trees, ferns and other plants that lived 300 to 400 million years ago. In some areas, such as portions of what-is-now the eastern United States, coal was formed from swamps covered by sea water. The sea water contained a large amount of sulfur, and as the seas dried up, the sulfur was left behind in the coal. Today, scientists are working on ways to take the sulfur out of coal because when coal burns, the sulfur can become an air pollutant. (To find out about these methods, see the section " Cleaning Up Coal .") Some coal deposits, however, were formed from freshwater swamps which had very little sulfur in them. These coal deposits, located largely in the western part of the United States, have much less sulfur in them.   All of these fossil fuels have played important roles in providing the energy that every man, woman, and child in the the United States uses. With better technology for finding and using fossil fuels, each can play an equally important role in the future. To read more about these fuels � both past and present � click on:

What kind of tide appears at full Moon?

Tides, and the pull of the moon and sun | Earth | EarthSky Tides, and the pull of the moon and sun By Deborah Byrd in Earth | April 7, 2016 The sun, the moon, the shape of a beach and larger coastline, the angle of a seabed leading up to land, and the prevailing ocean currents and winds all affect the height of the tides. This beautiful image is from EarthSky Facebook friend John Lloyd Griffith We all know the moon is primarily responsible for the rising and falling of ocean tides. In most places, but not everywhere, there are two high tides and two low tides a day. For any particular spot on Earth’s surface, the height of the tides and their fluctuation in time depends not only on the moon, but also on the sun – and also on the shape of the specific beach, the larger coastline, the angle of the seabed leading up to land, and the prevailing ocean currents and winds. The difference in height between high and low waters varies as the moon waxes and wanes from new to full and back to new again. The larger tides are called spring tides (nothing to do with season of spring). The smaller tides are called neap tides. Click the links below to learn more about the tides. Why are there two high tides and two low tides each day? Around each new moon and full moon – when the sun, Earth, and moon are located more or less on a line in space – the range between high and low tides is greatest. These are called spring tides. Image via physicalgeography.net What are spring tides? Around each new moon and full moon, the sun, Earth, and moon arrange themselves more or less along a line in space. Then the pull on the tides increases, because the gravity of the sun reinforces the moon’s gravity. In fact, the height of the average solar tide is about 50% the average lunar tide. Thus, at new moon or full moon, the tide’s range is at its maximum. This is the spring tide: the highest (and lowest) tide. Spring tides are not named for the season. This is spring in the sense of jump, burst forth, rise. So spring tides bring the most extreme high and low tides every month, and they happen around full and new moon. What are perigean spring tides? When the new moon or full moon closely aligns with perigee – closest point to Earth in the moon’s orbit – then we have an extra-large perigean spring tides . For example, in the year 2016, the April 7 new moon will closely align with perigee and the November 14 full moon will closely coincide with perigee, to bring forth perigean spring tides. When is the next supermoon? It’s when a spring tide coincides with a time of heavy winds and rain – flooding due to a weather extreme – that the most extreme flooding occurs. Around each first quarter moon and last quarter moon – when the sun and moon are at a right angle to Earth – the range between high and low tides is least. These are called neap tides. Image via physicalgeography.net What are neap tides? These sorts of tides occur halfway between each new and full moon – at the first quarter and last quarter moon phase – when the sun and moon are at right angles as seen from Earth. Then the sun’s gravity is working against the gravity of the moon, as the moon pulls on the sea. This is the neap tide: the tide’s range is at its minimum. Neap tides happen approximately twice a month, once around first quarter moon and once around last quarter moon. There’s about a seven-day interval between spring tides and neap tides. Earth has two tidal bulges, one of the side of Earth nearest the moon (where the moon’s gravity pulls hardest), and the other on the side of Earth farthest from the moon (where the moon’s gravity pulls least). Why are there two high tides and two low tides each day? If the moon is primarily responsible for the tides, why are there two high tides and two low tides each day in most places, for example, the U.S. eastern seaboard? It seems as if there should just be one. If you picture the part of Earth closest to the moon, it’s easy to see that the ocean is drawn toward the moon. That’s because gravity depends in part on how close two

What is the term given to the study of the weather?

What do you call a person who studies weather? | Reference.com What do you call a person who studies weather? A: Quick Answer A person who uses scientific methods to study, observe or forecast atmospheric patterns and weather events is known as a meteorologist. This field can be further divided into a number of differing job types, including broadcasting, teaching, researching and forensic meteorology. Full Answer The most common undergraduate degrees associated with this profession include physics, chemistry and mathematics prior to attaining an advanced degree in meteorology. Known as "the science of the atmosphere," a meteorologist is tasked with predicting the shifts in weather and climate that can affect the lives of the public. Many meteorologists work closely with other Earth scientists, including oceanographers and hydrologists, while communicating vital weather information to governments, media outlets and industry leaders.

What is the name given to the outermost layer of the Earth?

What is the outer layer of the Earth called? | Reference.com What is the outer layer of the Earth called? A: Quick Answer Containing everything from the ocean basins to continents, the crust is the outermost layer of the Earth. Overall, the crust makes up very little of the Earth's mass, so the other layers, which are the mantle, outer core and inner core, are much thicker. Full Answer Metamorphic, igneous and sedimentary rocks appear on the Earth's crust. At most, the crust's thickness is about 45 miles, and beneath that is a section of semi-solid rock, known as the mantle. Beneath the mantle is the Earth's outer core, which is a liquid layer of iron, and the inner core, which is a solid layer of iron and nickel under extreme pressure.

Which country produces the world's largest quantity of municipal waste per person per year?

Global Municipal Solid Waste Continues to Grow | Worldwatch Institute Global Municipal Solid Waste Continues to Grow OECD nations generate over two kilograms of municipal solid waste per person every day.  (Photo credit: WRS Italia) Growing prosperity and urbanization could double the volume of municipal solid waste annually by 2025, challenging environmental and public health management in the world’s cities, according to new research conducted for our Vital Signs Online service. Although some of this waste is eventually recycled, the doubling of waste that current projections indicate would bring the volume of municipal solid waste—or MSW—from today’s 1.3 billion tons per year to 2.6 billion tons. As defined in the report, MSW consists of organic material, paper, plastic, glass, metals, and other refuse collected by municipal authorities, largely from homes, offices, institutions, and commercial establishments. MSW is a subset of the larger universe of waste and typically does not include waste collected outside of formal municipal programs. Nor does it include the sewage, industrial waste, or construction and demolition waste generated by cities. And of course MSW does not include rural wastes. MSW is measured before disposal, and data on it often include collected material that is later diverted for recycling. MSW tends to be generated in much higher quantities in wealthier regions of the world. Members of the Organisation for Economic Co-operation and Development  (OECD), a group of 34 industrialized nations, lead the world in MSW generation, at nearly 1.6 million tons per day. By contrast, sub-Saharan Africa produces less than one eighth as much, some 200,000 tons per day. The list of top 10 MSW-generating countries includes four developing nations (Brazil, China, India, and Mexico) in part because of the size of their urban populations and in part because their city dwellers are prospering and adopting high-consumption lifestyles. Although the United States leads the world in MSW output at some 621,000 tons per day, China is a relatively close second, at some 521,000 tons. Even among the top 10, however, there is a wide range of output: the United States generates nearly seven times more urban refuse than France, in tenth position, does. Urbanization and income levels also tend to determine the type of waste generated. The share of inorganic materials in the waste stream, including plastics, paper, and aluminum, tends to increase as people grow wealthier and move to cities. Waste flows in rural areas, in contrast, are characterized by a high share of organic matter, ranging from 40 to 85 percent.Similarly, organic waste accounts for more than 60 percent of MSW in low-income countries, but only a quarter of the waste stream in high-income countries. Roughly a quarter of the world’s garbage is diverted to recycling, composting, or digestion—waste management options that are environmentally superior to landfills and incinerators. Recycling rates vary widely by country. In the United States, the recycled share of MSW grew from less than 10 percent in 1980 to 34 percentin 2010, and similar increases have been seen in other countries, especially industrial ones. The growing interest in MSW recovery is driven by a maturation of regulations and of markets for post-consumer materials. The global market for scrap metal and paper is at least $30 billion per year, according to the World Bank . The UN Environment Programme  (UNEP) estimates the market for waste management, from collection through recycling, to be some $400 billion worldwide. Yet UNEP also estimates that to “green” the waste sector would require, among other things, a 3.5-fold increase in MSW recycling at the global level, including nearly complete recovery of all organic material through composting or conversion to energy. The gold standard for MSW will be to integrate it into a materials management approach known as a “circular economy,” which involves a series of policies to reduce the use of some materials and to reclaim or recycle most of the rest. Japan h

Which sea is so highly polluted that the Barcelona Convention was set up in 976 to try and clean it up?

Hotel Barcelona Princess, Spain - Booking.com 8.8   One of our top picks in Barcelona. This property is 7 minutes walk from the beach. Barcelona Princess Hotel is a 10-minute walk from the beach in the city’s Forum area. It offers wonderful views, a free sauna and a gym. Free WiFi is available throughout. All guests have free access to the 2 heated outdoor pools. The one on the 23rd floor offers spectacular sea views. Rooms at Princess Barcelona are elegant and bright. Each has contemporary décor. All rooms have satellite TV and offer free drinks from the minibar. The hotel has a Mediterranean restaurant and 2 stylish bars, including a relaxed poolside bar with panoramic views. Princess Hotel Barcelona is set on Avenida Diagonal, next to Diagonal Mar Shopping Centre. The tour bus stops in front of the hotel and Maresme Forum Metro Station is 100 yards away. Plaza de Catalunya and Las Ramblas can be reached in 15 minutes, by Metro. Sant Martí is a great choice for travellers interested in beaches, monuments and city trips. This property is also rated for the best value in Barcelona! Guests are getting more for their money when compared to other properties in this city. We speak your language! Barcelona Princess has been welcoming Booking.com guests since 23 Jul 2004. Hotel Rooms: 364, Hotel Chain: Princess Most popular facilities Read more Booking.com guest review guidelines To keep the rating score and review content relevant for your upcoming trip, we archive reviews older than 24 months. Only a customer who has booked through Booking.com and stayed at the property in question can write a review. This lets us know that our reviews come from real guests, like you. Who better to tell others about the free breakfast, friendly staff, or quiet room than someone who’s stayed at the property before? We want you to share your story, both the good and the bad. All we ask is that you follow a few simple guidelines. Reviews vision We believe review contributions and property responses will highlight a wide range of opinion and experiences, which are critical in helping guests make well-informed decisions about where to stay. Reviews principles Contributions to Booking.com are a reflection of the dedication of our guests and properties, and are treated with the utmost respect. Whether negative or positive, we will post every comment in full and as quickly as possible, provided the guidelines are met. We will also provide transparency over the status of submitted content. We will use the same guidelines and standards for all user-generated content as well as the property replies to that content. We will allow the contributions to speak for themselves, and we won’t be the judge of reality. Booking.com’s role is that of a distributor of feedback from both guest and property. Guidelines and standards for Reviews These guidelines and standards aim to keep the content on Booking.com relevant and family-friendly without limiting expression of strong opinions. They are also applicable regardless of the sentiment of the comment. Contributions should be travel related. The most helpful contributions are detailed and help others make better decisions. Please don’t include personal, political, ethical, or religious commentary. Promotional content will be removed and issues concerning Booking.com’s services should be routed to our Customer Service or Accommodation Service teams. Contributions should be appropriate for a global audience. Please avoid using profanity or attempts to approximate profanity with creative spelling, in any language. Comments and media that include 'hate speech', discriminatory remarks, threats, sexually explicit remarks, violence, and the promotion of illegal activity are not permitted. All content should be genuine and unique to the guest. Reviews are most valuable when they are original and unbiased. Your contribution should be yours. Booking.com property partners should not post on behalf of guests or offer incentives in exchange for reviews. Attempts to bring down the rating of a competitor by submitting a negativ

What is the scientific scale for measuring the hardness of rocks?

Bestcrystals.com . Mohs Hardness Scale Mohs Hardness Scale Mohs Hardness Scale The hardness of a stone is one of the properties that contribute to identification.  Hardness is also an attribute which is important to be aware of, because it may determine what a stone may be used for (jewelry, carving, faceting, handling, storage, etc.)  You may want to familiarize yourself with the Mohs Scale of Hardness.  This will help you understand the relationships between stones according to their hardness.  The Mohs Scale of Hardness consists of 10 classifications, 1 being the softest, and 10 being the hardest.  The only mineral that is an exception to this is mercury, which is liquid.  To give you a few reference points, the diamond is of course the hardest, rated 10.  Your fingernail is a 2, a pocket knife is about a 5-6, and a piece of glass is a 6-7.  Each classification will scratch the one preceding it.  As you know, a diamond (10) will scratch glass (6-7).  This technique is commonly used in the field for initial identification, and it is good to have samples of some of these stones with you in order to perform the test.  Some minerals have varying hardness according to the direction you may scratch them in, but typically this is either hardly detectable or an exception to the rule. The following, is a partial listing of stones and their hardness classification: 1

What is the world's smallest continent?

Which Continent Is the the World's Smallest? By Matt Rosenberg Updated August 10, 2016. There are seven continents in the world and Asia is the largest , but which one is the smallest? The answer is Australia and it is almost a fifth of the size of Asia. Europe is not far behind, though, as it has just over a million more square miles than Australia. If we are looking at population, Australia is also at the bottom of the list of continents with permanent residents. Of course, Antarctica is the least populated continent because only a few thousand researchers call it a temporary home. Just How Small is Australia? In terms of land area, the continent of Australia is the world's smallest continent. In total, it includes 2,967,909 square miles (7,686,884 square kilometers), which is slightly smaller than the country of Brazil as well as the contiguous United States. Europe is the second smallest continent in area at 3,997,929 square miles (10,354,636 square kilometers). Antarctica is the third smallest continent in area at approximately 5,500,000 square miles (14,245,000 square kilometers). When it comes to population, technically Australia is the second smallest continent. If we exclude Antarctica, then Australia is the smallest. We might say that Australia is the smallest populated continent. Antarctica - Has no permanent residents though up to 4000 researchers and personnel live there in the summer and 1000 stay through the winter. Australia - 39,506,070 (all of Oceania) South America - 413,869,568 (Population count as of 2015 via the Population Reference Bureau (PRB) .) But Australia is Also the Largest... Australia is an island since it's surrounded by water but it is also large enough to be considered a continent. Though technically a continent, Australia may be considered the largest island in the world. In most cases, Greenland is accepted as the largest in the world . The country of Australia is the world's sixth-largest country on earth. Australia is the largest country that is entirely in the Southern Hemisphere. Australia is also the largest country without land borders. Among the inhabited continents, Australia has the driest continent. Australia's Relationship to Oceania Is Australia part of Oceania? This is a question of much debate and it depends on your definition of Oceania.  Oceania refers to the Pacific island region of the world that includes all of the small islands near Australia. It can be divided many ways and quite often, Australia is included in a sub-group of Oceania known as Australasia (Australia and New Zealand). Quite often, when referring to this southern Pacific region, people will use the term 'Australia and Oceania' rather than adding Australia into Oceania.

Which gas forms approximately 1% of the atmosphere?

Introduction to the Atmosphere: Background Material Introduction to the Atmosphere This section provides a brief overview of the properties associated with the atmosphere. The general concepts found in this section are: The earth's atmosphere is a very thin layer wrapped around a very large planet. Two gases make up the bulk of the earth's atmosphere: nitrogen ( ), which comprises 78% of the atmosphere, and oxygen ( ), which accounts for 21%. Various trace gases make up the remainder. Based on temperature, the atmosphere is divided into four layers: the troposphere, stratosphere, mesosphere, and thermosphere. Energy is transferred between the earth's surface and the atmosphere via conduction, convection, and radiation. Ocean currents play a significant role in transferring this heat poleward. Major currents, such as the northward flowing Gulf Stream, transport tremendous amounts of heat poleward and contribute to the development of many types of weather phenomena. This section includes seven classroom activities. Atmospheric Properties The thin envelope of air that surrounds our planet is a mixture of gases, each with its own physical properties. The mixture is far from evenly divided. Two elements, nitrogen and oxygen, make up 99% of the volume of air. The other 1% is composed of "trace" gases, the most prevalent of which is the inert gaseous element argon. The rest of the trace gases, although present in only minute amounts, are very important to life on earth. Two in particular, carbon dioxide and ozone, can have a large impact on atmospheric processes. Another gas, water vapor, also exists in small amounts. It varies in concentration from being almost non-existent over desert regions to about 4% over the oceans. Water vapor is important to weather production since it exists in gaseous, liquid, and solid phases and absorbs radiant energy from the earth. Structure of the Atmosphere The atmosphere is divided vertically into four layers based on temperature: the troposphere, stratosphere, mesosphere, and thermosphere. Throughout the Cycles unit, we'll focus primarily on the layer in which we live - the troposphere. Troposphere The word troposphere comes from tropein, meaning to turn or change. All of the earth's weather occurs in the troposphere. The troposphere has the following characteristics. It extends from the earth's surface to an average of 12 km (7 miles). The pressure ranges from 1000 to 200 millibars (29.92 in. to 5.92 in.). The temperature generally decreases with increasing height up to the tropopause (top of the troposphere); this is near 200 millibars or 36,000 ft. The temperature averages 15°C (59°F) near the surface and -57°C (-71°F) at the tropopause. The layer ends at the point where temperature no longer varies with height. This area, known as the tropopause, marks the transition to the stratosphere. Winds increase with height up to the jet stream. The moisture concentration decreases with height up to the tropopause. The air is much drier above the tropopause, in the stratosphere. The sun's heat that warms the earth's surface is transported upwards largely by convection and is mixed by updrafts and downdrafts. The troposphere is 70% Atmospheric Processes Interactions - Atmosphere and Ocean In the Cycles overview, we learned that water is an essential part of the earth's system. The oceans cover nearly three-quarters of the earth's surface and play an important role in exchanging and transporting heat and moisture in the atmosphere. Most of the water vapor in the atmosphere comes from the oceans. Most of the precipitation falling over land finds its way back to oceans. About two-thirds returns to the atmosphere via the water cycle. You may have figured out by now that the oceans and atmosphere interact extensively. Oceans not only act as an abundant moisture source for

What is the term for the energy obtained from hot, underground rocks?

Hot Rock Energy - What is Hot Rock Energy? Hot Rock Energy What is Hot Rock Energy? Geothermal Energy | Hot Rock Energy | Hot Dry Rocks | Enhanced Geothermal Resources Classical Geothermal energy is widely regarded as describing the process of using hot water or steam extracted from geothermal reservoirs in the earth's crust, created by upward convection and conduction of heat from the Earth’s mantle and core, that can be used for geothermal heat pumps, water heating, or electricity generation. Hot Dry Rock (HDR) describes the process of extracting heat from deep crystalline rock heated by the decay of radioactive elements including uranium, thorium, and potassium isotopes in effect - nature's nuclear power plant. In recognition of the recent discovery that these target rocks aren't dry the newer term Hot Rock Energy is beginning to gain dominance. Enhanced Geothermal System (EGS) describes  Hot Rock Energy sytems with "engineered" heat exchangers where the hot rocks have been fractured to allow for enhanced fluid volumes and flow. Images of Hot Rock Energy Systems   Note the timelines for Geothermal Hot Rock that predict that Hot Rock Energy will be amongst, if not, the first of the non-coal "baseload" Alternative Energy systems to be deployed Hot Rock Energy will provide the cheapest green baseload electricity emission free production system   The amount of money spent on Hot Rock Energy is rapidly increasing http://www.pir.sa.gov.au/geothermal Hot Rock Energy | EGS* - Enhanced Geothermal Resource A type of geothermal power production system that utilizes the very high temperatures that can be found in rocks a few kilometers below ground. This is done by pumping high pressure water down a borehole into the heat zone. The water travels through fractures of the rock, capturing the heat of the rock until it is forced out of a second borehole as very hot water – the thermal energy of which is converted into electricity using either a steam turbine or a binary power plant system. All of the water, then cooled, is injected back into the ground to heat up again. Since the 1970s, research projects aimed at developing techniques for the creation of geothermal reservoirs are being conducted around the world. These include the following: • United States: Fenton Hill, Coso, Desert Peak, Glass Mountain, and The Geysers/Clear Lake • United Kingdom: Rosemanowes • France: Soultz, Le Mayet de Montagne • Japan: Hijiori and Ogachi • Australia: Cooper Basin, Hunter Valley, and others • Sweden: Fjallbacka • Germany: Falkenberg, Horstberg, and Bad Urach • Switzerland: Basel and Geneva More on Geothermal Historical Development Timelines The potential rewards for Australia of having almost limitless, green, base load electricity have been well recognised by our current Labor Government and several parliament members are actively promoting funding for research and ongoing development. A lot of interest is also being generated overseas and a 2007 paper, excerpted below, encapsulates many of the benefits that apply to both the USA and Australia. The Future of Geothermal Energy (USA 2007) -Impact of Enhanced Geothermal Systems on the United States in the 21st Century. An assessment by the MIT-led interdisciplinary panel. Read full paper "When examining the full life cycle of geothermal energy developments, their overall environmental impacts are markedly lower than conventional fossil-fired and nuclear power plants. In addition, they may have lower impacts in comparison to other renewables such as solar, biomass, and wind on an equivalent energy-output basis. This is primarily because a geothermal energy source is contained underground, and the surface energy conversion equipment is relatively compact, making the overall footprint of the entire system small. EGS geothermal power plants operating with closed-loop circulation also provide environmental benefits by having minimal greenhouse gas and other emissions. Being an indigenous resource, geothermal – like other renewable resources – can reduce our dependence on imported fossil fuels. As it pr

What name is given to the rocks swallowed by dinosaurs to assist their digestion?

Dinosaurs 118 Final - Science 118 with Oliver at Worcester State College - StudyBlue Who was the last Ptolemaic Pharaoh? Cleopatra Which of the Greek elements was the lightest? Fire The fall of what city was the ultimate (albeit distant) justification given for the first crusade? Jerusalem When did the universe begin (roughly)? 14 billion years ago Who was the tutor of Alexander, Prince of Macedon? Aristotle Identify the scientist associated with: Astrology Ptolemy What Greek city is the home of the Pythian Oracle of Apollo? Delphi The statement "We can't prove Aliens didn't build the pyramids, therefore they did" is an example of the appeal to stupidity. True or False? False An appeal to authority is legitimate if 1) The authority is an expert in the area of knowledge under consideration; and 2) The statement of the authority concerns his or her area of mastery; and 3) You happen to like the experts point of view. True or False? False If we pass laws against fully-automatic weapons, then it won't be long before we pass laws on all weapons, and then we will begin to restrict other rights, and finally we will end up living in a communist state. Thus we should not ban fully automatic weapons. What kind of argument is this? A slippery slope argument The argument fallacy hat means attacking the person instead of the argument is: Ad hominem Anecdotes are valid evidence. True or False? False "Science is built of facts the way a house if built of bricks; but an accumulation of facts is no more science than a pile of bricks is a house." - Who said this? Henri Poincaire Tautaology, circular reasoning, and 'avoiding the question' all mean the same thing. True or False? False Treating a complex issue as if there are only two, polar opposite choices is called: False Dichotomy 'Circular reasoning' is using a restatement of your conclusions as your premise. True or False? True What is the term for a faulty logical argument? Fallacious The fallacy occurs when we selectively focus on the evidence which tends to make our case while ignoring counter-examples is called: Confirmation Bias The fallacy of exclusion violates the total evidence principle. True or False? True Statement 1: All squares are rectangles. This is a square, therefore it is a rectangle. Statement 2: This is a rectangle, therefore it is a square. Statement 2 is an example of a: Non-reciprocal syllogism If, because we don't know something DIDN'T happen, we can conclude that it DID happen, then we have committed the appeal to: Ignorance Using 'expert' testimony to make your case is called; Appeal to Authority Dr. Oliver's observation that "people don't usually answer the question they are being asked" is known as 'avoiding the question.' True or False? True The latin term for a conclusion that "doesn't follow' from a premise is; Non sequitur Using an unrelated argument to distract from the case being debated is called a; Red Herring What Family includes leopards and domestic cats? Felidae According to the concept of punctuated equilibrium, a new species accumulates most of its unique features as it comes into existence Who is the creator of the cladistic method? Willi Hennig Is only found in only one group AND all members of the group possess it What order contains dogs, cats, bears, and weasels? Carnivora Sabertooth mammals are a _______ assemblage? Polyphyletic What term means a clade derived from multiple ancestors? Polyphyly The defininf character of the Vertebrata is Vertebrae The biological species concept is inadequate for grouping asexual organisms What group lost their eyes, and later re-evolved them? Snakes Chordates do not include what... echinoderms The term that is most appropriately associated with clade is... monophyletic If flight is a character used to group two distantly related organisms, it would be what kind of trait? Homoplastic Who wrote the book "Zoonomia" proposing evolution? Darwin's grandfather, Erasmus Darwin A tentative explanation that can be tested and is falsifiable. Who wrote the Essay on Population that so affected Darwin's thi

Which animal has been hunted almost to extinction because of its horn?

6 endangered animals poachers are hunting into extinction FacebookEmail Twitter Google+ LinkedIn Pinterest 6 endangered animals poachers are hunting into extinction The killing of Cecil the lion, one of Zimbabwe’s most loved wild animals, is just the tip of the iceberg when it comes to the thousands of animals taken by poachers each year. Post to Facebook 6 endangered animals poachers are hunting into extinction The killing of Cecil the lion, one of Zimbabwe’s most loved wild animals, is just the tip of the iceberg when it comes to the thousands of animals taken by poachers each year. Check out this story on USATODAY.com: http://usat.ly/1SocYFu CancelSend A link has been sent to your friend's email address. Posted! A link has been posted to your Facebook feed. 4 To find out more about Facebook commenting please read the Conversation Guidelines and FAQs 6 endangered animals poachers are hunting into extinction Jessica Phelan, GlobalPost Published 11:34 a.m. ET July 31, 2015 | Updated 2:55 p.m. ET July 31, 2015 A staff member with the Kenya Wildlife Services does an inventory of illegal elephant ivory stockpiles at its headquarters in Nairobi on July 21, 2015. (Photo: Tony Karumba, AFP/Getty Images) The killing of Cecil the lion, one of Zimbabwe’s most loved wild animals, is just the tip of the iceberg when it comes to the thousands of animals taken by poachers each year. Some are killed by hunters, others by organized criminals who want to sell different parts. Sometimes, it's impoverished people looking for easy cash or even a meal. Whatever poachers’ motivations, they’re threatening to wipe some of the most vulnerable species off the face of the earth. Here are six animals that, like Cecil, poaching might rob us of forever. ELEPHANTS  (Photo: Ben Curtis, AP) Poachers are  the single biggest threat  to elephants’ survival. After decades of decimation of elephant populations for their ivory, the international trade in “white gold” was banned in 1989. Yet people’s persistent willingness to hand over bigger and bigger sums of money for dead elephant tusk — in China,  $2,100 per 2.2 pounds  on average as of last year — has made it more tempting than ever for profit seekers to kill elephants illegally. The most comprehensive  survey  to date stated that 100,000 African elephants were poached across the continent between 2010 and 2012. According to those figures, in 2011 alone poachers killed roughly one in every 12 African elephants. Sometimes elephant poachers use bows and arrows as their weapon of choice. Sometimes they tip the arrows with poison, like the people who last year slaughtered one of Kenya’s most famous elephants,  Satao , and hacked off his magnificent 6.5-foot tusks. Other hunting expeditions have seen  gangs turn grenades and AK-47s on entire herds , even within the supposed shelter of national parks. Asian elephants , considered an even more vulnerable species, are also hunted for their tusks, body parts, meat and hide. Unlike their African cousins, only male Asian elephants have tusks — a fact that makes the consequences of poaching even more devastating, since the selective killings of bulls creates a gender imbalance and thereby reduces reproduction in the remaining population. RHINOS  (Photo: Tony Karumba, AFP/Getty Images) Rhinoceroses, like elephants, suffer the misfortune of having an external protrusion that humans arbitrarily place a high value upon. Rhino horn was reported to be selling for  $65,000 per 2.2 pounds  in 2012, making it more expensive by weight than gold, diamonds or cocaine. The demand comes from Southeast Asia, particularly Vietnam, where some people believe that consuming rhino horn will cure everything  from cancer to hangovers . The black market demand for rhino horn has led to a surge in poaching of the critically endangered black rhino and the more numerous southern white rhino across southern Africa since 2008. This is especially the case in South Africa, where illegal killings hit  another record high  at 393 in the 12 months leading up to April. And that’s not counting legal

Which chemical, commonly used to increase crop yield, sometimes contaminates drinking water?

Potential Carcinogens in Your Drinking Water and How to Test for Contamination Bringing Drinking Water & Insight To The World Cancer Awareness: “Top Ten” Potential Risks in Your Drinking Water (Part 1 of 2) by wfnblog on October 20, 2011 Many of us are increasingly unsettled about the potential harm of a growing number of contaminants in tap water, especially those which adversely impact human health. Since the 1970s, sampling for water pollutants has markedly increased. Now hundreds of manufactured chemicals have been found in the groundwater and various other drinking water sources. Chemical contamination of drinking water can be traced to several different causes, including wrongful disposal of household cleaners, leaking underground storage tanks, seepage from landfills, discharge from factories and increased pesticide & fertilizer use over the past fifty years. As troubling as the discovery of contaminated drinking water is, it’s a more hopeful sign that in recent decades, laboratories have become much more finely skilled in detecting a long list of chemicals. More importantly, our scientific knowledge of the health risks linked to drinking water contaminants has also improved. As a result, various home water treatment options are now widely available for reducing exposure to chemicals in tap water. Some contaminants are known to cause cancer in the human population.  Others are suspected culprits. These contaminants are commonly referred to as carcinogens. When the Environmental Protection Agency (EPA) establishes primary drinking water standards for carcinogens, the EPA acknowledges that no concentration in drinking water is safe, but it also must decide what level of risk is tolerable for the purpose of regulation. For many carcinogens, the concentration in drinking water causing no more than one cancer per million is typically in the range of a few parts per billion.  Although more research continues to be done on an ongoing basis, here are our current “top ten” contaminants of possible concern: Synthetic Organic Chemicals: Pesticides, Fertilizers, THMs, VOCs, Solvents 1. Pesticides are manufactured by humans from carbon, chlorine, hydrogen, nitrogen and other elements for a variety of purposes. The health effects of pesticides depend on their chemical characteristics. The use of pesticides, which include insecticides, herbicides and fungicides, is widespread in commercial farming and residential landscaping. Pesticides enter the groundwater during accidental spills, improper application, illegal dumping, manufacturing discharge or excessive rainfall after normal application. These agricultural chemicals can contain substances that disrupt the endocrine system. Some of these chemicals break down very slowly,  so they persist in the environment—even in non-agricultural areas. 2. Fertilizers are another group of chemicals commonly used in agriculture to increase crop yield. Fertilizer by-products, formed as a result of natural chemical processes, however, can be potentially carcinogenic. These agricultural chemicals are one of the major sources of water pollution. For instance, the nitrogen in fertilizers gets converted into nitrate that seeps into groundwater. When ingested, nitrates form nitrosamines which have been found to cause tumor growths in animal studies. 3. Water Disinfection By-Products (THMs) are another issue. Although disinfection of the drinking water supply with chemicals like chlorine has dramatically reduced outbreaks of waterborne illnesses and deaths, research has suggested that long-term exposure to disinfection by-products may elevate cancer risk. Hundreds of disinfection by-products have been identified, but only a few are monitored. Even fewer have been tested for carcinogenicity. One common category of by-products are trihalomethanes, which form when chlorine and/or bromine combine with organic material in the water, such as decomposing leaves or animal waste. Some examples of THMs that may exist in drinking water are chloroform and bromoform. 4. Volatile Organic Compounds (VOCs) are chem

When you recycle a drink can, which metal is it you are recovering?

How to Recycle Metals: 6 Steps (with Pictures) - wikiHow How to Recycle Metals Community Q&A Recycling metal items from your household waste is an excellent way to save energy and help reduce the waste piles. This article provides an overview of which metals you can recycle and the forms that you're likely to find them in in your household; it will also provide some advice on what is likely not to be recyclable at most recycling depots! Steps 1 Contact local recycling facilities to see what is available to you, what types of materials they accept, and other guidelines they may have. Once you have done this, you can look for good materials to bring in for recycling. 2 Recycle aluminum . Aluminum is very lucrative for the recycling companies and recycled aluminum requires only 5 percent of the energy required for making it from scratch. Here are some of the items to consider recycling: Aluminum candy bar wrappers. Note that many wrappers might look like aluminum, but are actually tin foil and may not be recyclable. Ask your recycling facility. Aluminum plates Brass 6 Know which metals are not recyclable. There are a number of metallic items that won't be recyclable at most depots (although it never hurts to ask). The following items provide an idea of what is mostly likely not recyclable: Containers used for paint or aerosols - dispose of properly Toxic products - must be disposed of properly in accordance with relevant laws Clothes hangers (but there is a range of amazing things you can reuse these for, like a panty hose sculpture and more !) Your local dry cleaners may take hangers. Pieces of metal - make craft from scrap metal where possible Pipes (unless they are copper) Community Q&A If this question (or a similar one) is answered twice in this section, please click here to let us know. Video This video provides a few tips on recycling frozen juice containers, which contain plastic and cardboard in addition to metal. Tips Check out metal prices online to see whether or not you should be recycling for profit or just for doing a good deed. Note that what can and cannot be recycled depends on your local recycling capacities. Some of the items in this article may or may not be recyclable in your region, dependent on recycling capacity. This guide is general in nature; it pays to call and find out what is accepted. Things You'll Need Recycling depot Information about what your local depot does and does not accept for recycling; this differs from region to region and country to country and is dependent on demand

What is the name of the liquid rock which pours from a volcano?

What is the name of the liquid rock which pours from a volcano? - YouTube What is the name of the liquid rock which pours from a volcano? Want to watch this again later? Sign in to add this video to a playlist. Need to report the video? Sign in to report inappropriate content. The interactive transcript could not be loaded. Loading... Rating is available when the video has been rented. This feature is not available right now. Please try again later. Published on Aug 1, 2013 This improves the knowledge of the children indirectly as they never know that they are learning. - Category

What is the term applied to the process of gathering together weather forecasts from various recording stations?

Weather Forecasting facts, information, pictures | Encyclopedia.com articles about Weather Forecasting COPYRIGHT 2003 The Gale Group, Inc. Weather forecasting Weather forecasting is the attempt by meteorologists to predict the state of the atmosphere at some future time and the weather conditions that may be expected. Weather forecasting is the single most important practical reason for the existence of meteorology as a science. It is obvious that knowing the future of the weather can be important for individuals and organizations. Accurate weather forecasts can tell a farmer the best time to plant, an airport control tower what information to send to planes that are landing and taking off, and residents of a coastal region when a hurricane might strike. Humans have been looking for ways to forecast the weather for centuries. The Greek natural philosopher Theophrastus wrote a Book of Signs, in about 300 b.c. listing more than 200 ways of knowing when to expect rain, wind , fair conditions, and other kinds of weather. Scientifically-based weather forecasting was not possible until meteorologists were able to collect data about current weather conditions from a relatively widespread system of observing stations and organize that data in a timely fashion. By the 1930s, these conditions had been met. Vilhelm and Jacob Bjerknes developed a weather station network in the 1920s that allowed for the collection of regional weather data. The weather data collected by the network could be transmitted nearly instantaneously by use of the telegraph, invented in the 1830s by Samuel F. B. Morse. The age of scientific forecasting, also referred to as synoptic forecasting, was under way. In the United States , weather forecasting is the responsibility of the National Weather Service (NWS), a division of the National Oceanic and Atmospheric Administration (NOAA) of the Department of Commerce. NWS maintains more than 400 field offices and observatories in all 50 states and overseas. The future modernized structure of the NWS will include 116 weather forecast offices (WFO) and 13 river forecast centers, all collocated with WFOs. WFOs also collect data from ships at sea all over the world and from meteorological satellites circling Earth . Each year the Service collects nearly four million pieces of information about atmospheric conditions from these sources. The information collected by WFOs is used in the weather forecasting work of NWS. The data is processed by nine National Centers for Environmental Prediction (NCEP). Each center has a specific weather-related responsibility: seven of the centers focus on weather prediction—the Aviation Weather Center, the Climate Prediction Center, the Hydrometeorological Prediction Center, the Marine Prediction Center, the Space Environment Center, the Storm Prediction Center, and the Tropical Prediction Center—while the other two centers develop and run complex computer models of the atmosphere and provide support to the other centers—the Environmental Prediction Center and NCEP Central Operations. Severe weather systems such as thunderstorms, tornadoes, and hurricanes are monitored at the National Storm Prediction Center in Norman, Oklahoma , and the National Hurricane Center in Miami , Florida . Hurricane watches and warnings are issued by the National Hurricane Center's Tropical Prediction Center in Miami, Florida, (serving the Atlantic, Caribbean, Gulf of Mexico , and eastern Pacific Ocean ) and by the Forecast Office in Honolulu , Hawaii , (serving the central Pacific). WFOs, other government agencies, and private meteorological services rely on NCEP's information, and many of the weather forecasts in the paper, and on radio and television, originate at NCEP. Global weather data are collected at more than 1,000 observation points around the world and then sent to central stations maintained by the World Meteorological Organization, a division of the United Nations. Global data also are sent to NWS's NCEPs for analysis and publication. The less one knows about the way the atmosphere works the simp

What kind of natural phenomenon 'meanders'?

15 weird natural phenomena [PICS] - Matador Network 15 weird natural phenomena [PICS] by Sarah Park August 27, 2010 Sarah Park brings us some of the most dangerous, beautiful, and downright weird wonders of the natural world. 1 Bioluminescent red tide When conditions are just right, ocean phytoplankton reproduce like bunnies, creating a thick, visible layer near the surface. These algae blooms (a.k.a "red tide") might look disgusting during the day, but in parts of California and other places where the bioluminescent variety of Noctiluca scintillans bloom, red tide nights look out of this world. This particular variety of phytoplankton glows blue when agitated, transforming the dark ocean into a giant lava lamp. Watch the waves light up as they crash, run across the sand to see the ground glow under your feet, or dive in to be surrounded by the bizarre Timex-y glow. N. scintillans is also the culprit behind the Bioluminescent Bays in Puerto Rico . Photo: catalano82 2 Foxfire During the late summer, a faint, eerie glow can be seen in forests around the world, where bioluminescent mushrooms grow on moist, rotting bark. The greatest diversity of foxfire occurs in the tropics, where moist forests encourage fungal growth. The newest varieties of glow-in-the-dark mushrooms were introduced to the world just last year, after being collected from Ribeira Valley Tourist State Park near Sao Paulo, Brazil. To up your chances of seeing this one, hunt in the forest during its wettest season and move as far as possible from any artificial light sources. And f you happen to see a patch of glowing shrooms, don't even think about it -- they're not that kind of mushroom . Photo: Ylem 3 Fire rainbow Another summertime occurrence, fire rainbows appear when sunlight hits frozen ice crystals in high-altitude cirrus clouds. Because the fire rainbow actually involves no rain at all, scientists would rather we refer to this occurrence by its much less fun, but much more accurate title: the circumhorizonal arc. Since the arc requires both the presence of cirrus clouds and for the sun to be extremely high in the sky, it's much more likely to be seen at latitudes closer to the equator. Conditions might be right for a fire rainbow in Los Angeles six months out of the year, but in a more northern city like London, that window drops to a mere two months. The photo above was taken in West Virginia . Photo: Jeff Kubina Intermission 4 Nacreous clouds For those of you a bit farther away from the equator, there's still plenty to see in the sky. Nacreous clouds (also called mother-of-pearl clouds) are extremely rare, but unmistakeable in the dark hours before dawn or after sunset. Because of their extremely high altitudes, they reflect sunlight from below the horizon, shining it down brightly, in stark comparison to the regular ol' dark clouds in the troposphere. The lower stratosphere, where nacreous clouds live, is so dry that it often prevents cloud formation, but the extreme cold of polar winters makes this beautiful phenomenon possible. Captured best during winter at high latitudes, nacreous clouds have been spotted in Iceland , Alaska, Northern Canada, and very rarely, farther south in England. Photo: Thomas Larsen Røed 5 Snow rollers Snow rollers are formed when a thick layer of snow falls on top of a layer of ice. If the temperature and wind speed are right, chunks of snow can break loose and start rolling. As they're blown along the ground like wintry tumbleweeds, they pick up additional snow along the way. The inner layers are often weaker and less compact, allowing them to be blown easily away by the wind, leaving a large, naturally formed snow donut. Because of the precise temperature and wind speeds required to create this effect, snow rollers are a rare sight, but have made headlines with their appearances in parts of North America and the UK . Photo: jah~ 6 Columnar basalt A natural volcanic formation, columnar basalt has a seemingly man-made appearance. The (mostly) hexagonal columns form naturally as thick lava rapidly cools, contract

What is the collective name for rain hail, snow, and sleet?

Hail or Sleet, How to Tell the Difference Hail or Sleet, How to Tell the Difference By By: Kristen Connolly February 21, 2013, 8:25:21 AM EST There are two easy facts to differentiate between hail and sleet: time of year and size. Using these essentials, it is easy to identify what kind of frozen precipitation is falling. Hail: Hail occurs during severe weather. Hail is the formed when an object, including dust or particles in the air, collides with supercooled water. As the water freezes around the object, it begins to form an ice pellet. To understand this, you have to remember that warm air rises and cool air sinks (the same as heating or cooling in your house) this is because colder air is more dense than warmer air. Normally, warm air is very buoyant in the clouds that are associated with thunderstorms. This buoyancy causes these clouds to rise higher into the atmosphere past the freezing level. The length of time the ice pellet stays in the cloud is a representation of how large it will be when it falls to the ground. How does it increase in size? Inside the cloud, there are a series of updrafts. The pellet will continue to be tossed up and down, adding layers of ice, until it becomes too heavy for the updraft. When the hail becomes too heavy, it then falls to the ground. Usually accompanying severe thunderstorms, hail can be a variety of sizes, many times correlating with the intensity of the thunderstorms. Certain hail can get as large as golf balls, softballs or even larger! The largest hailstone ever found was in Vivian, S.D., it weighed 1.9 pounds and measured 8 inches in diameter with an 18.5-inch circumference. Sleet Sleet occurs during winter weather and is a type of winter precipitation. All precipitation falls out of a cloud as snow. In certain instances, in the winter, the snowflake will go through a warmer layer and begin to melt. As it continues to fall, it will then proceed through a colder layer and freeze into an ice pellet or ball, very similar to hail. Unlike hail, the pellet only "falls" once and is generally very tiny in size.

What is the hardest natural substance known?

What is the hardest natural substance known? | Flexiguru What is the hardest natural substance known? Class 10th Chemistry Mahesh Kumar The hardest natural substance is diamond which is an allotrope of carbon. It has superlative physical qualities which originated from the strong covalent bonding between its atoms. The carbon atoms are arranged in a variation of the face-centred cubic crystal structure called a diamond lattice. Kamal Sharma Diamond. It's carbon packed extremely tightly together, which makes it pretty much unbreakable. This is also part of the reason why diamonds are so highly valued no one wants their diamond ring to fall to the ground and shatter into a million pieces. Diamond is currently thought to be the hardest natural material on Earth, having a hardness of ten out of ten on the Mohs scale of mineral hardness. Diamond is made up of carbon atoms which share strong covalent bonds (where electrons are shared between atoms) and are equally spaced in a lattice arrangement. These atoms cannot move, which is what makes diamonds so hard.

What is the collective noun for crows?

The Crow Society What do you call a grouping of Crows? A murder Many birds live alone, but crows live in a group called a murder. Most people would call it a Flock of Crows. One could think of a murder of Crows to be the "poetic term" .  The word for this grouping appears in the title of the short story  "Murders in the Rue Morgue" is a well-known short story by Edgar Allan Poe. This is all things to the "collective noun". In fact a murder is not the only collective noun for a grouping of crows. A horde, hover, muster, parcel are also listed as collective nouns for Crows. The most famous of them all is "a murder. A collective noun is a noun that is singular in formal shape but denotes a group of referents. These are also called group nouns. Sometimes, usually in grammatical discussions, collective noun is also used to refer to plural-only words such as people or cattle. It gets crazy when you start to look at all of the A collective nouns. Here are just a short list!

What is the maximum speed of a garden snail: 0.03 mph, 0.3 mph, or 3 mph?

Speed of a Snail - The Physics Factbook Speed of a Snail The World Almanac and Book of Facts 1999. New Jersey: Primedia, 1998: 572. "Garden snail, 0.03 mph" 0.013 m/s Branson, Branley Allan. World & I. 11, 5 (May 1996): 166. "A large banana slug has been observed to cover 6.5 inches in 120 minutes. At that rate, a tortoise would seem fleet-footed." 0.000023 m/s The Guinness Book of World Records 1998. Stanford, CT: Guinness, 1997: 144. "A garden snail named Archie, owned by Carl Branhorn of Pott Row, England, covered a 13 inch course in 2 minutes at the 1995 World Snail Racing Championships, held in Longhan, England." 0.0028 m/s Snails and slugs are gastropods, which make up the largest class of mollusks with more than 60,000 species. Most of these species can be identified by their shells. Some dwell in ocean, others in the freshwater of rivers, ponds, and lakes. Land snails abound in tropical jungles and in damp temperate regions. All of them need calcium carbonate for building their shells, and so are not common in sandy soil. Slugs differ from snails in that they generally have only a small internal shell. Snails move by sliding on their single foot. Specialized glands in the foot secrete mucus, which lubricates the path over which the snail crawls. Snails can only crawl. Even those that live in water can't swim. As they crawl they secrete a slime to help themselves move across surfaces. Snails and slugs travel at speeds that vary from slow (0.013 m/s) to very slow (0.0028 m/s). The snail's head bears the mouth opening and one or two pairs of tentacles. The eyes are located at the base of the tentacles. Most snails live off plants and dead organic matter, although a few are carnivorous. Their radula is a tongue-like projection of their mouth which is lined with small sharp teeth. Some snails obtain food by using their radula to drill holes in the shells of other mollusks. Freshwater snails and land snails have been eaten by people since prehistoric times. Today they are still regarded as a delicacy in many countries. The market supply comes largely from snails that are raised in captivity on special farms in southern France, Italy, and Spain. About 10,000 snails can be kept in a 9 square meter area, where they are fed meal, vegetables, and bran. Angie Yee -- 1999

What common mineral is formed by the fossilization of vegetation?

Rocks, Minerals, and Fossils Rocks, Minerals, and Fossils From Grolier's New Book of Popular Science A geologist studies a rock outcrop. Scott Orr/iStockphoto Rocks are subjected to a variety of physical and chemical conditions such as heat, weather, and erosion, which can change rocks from one kind to another. Grolier Growing up during the 1950s, Jack Horner wandered the hills and gullies of Montana, head down and eyes open, looking at rocks. At age 8, he found his first dinosaur bone. Today Horner is the world's best-known "dinosaur hunter." He searches for their fossil remains in rock beds from Mexico to Mongolia. Although few people will pursue rock or fossil hunting as a career, most everyone has, from time to time, stooped down to pick up an unusual rock, a pretty crystal, or a fossilized shell. This is hands-on geology, because the history of Earth is contained in its rocks, minerals, and fossils. Learning about their formation and forms can enhance one's appreciation of Earth's geologic history, and perhaps inspire a lifelong hobby. ROCKS Although almost everyone knows what a rock looks like, far fewer people can name its defining characteristics. A rock can be defined as a naturally formed solid that consists of particles of one or more natural substances such as mineral grains, glass, and fragments of plant debris. By the term "naturally formed," geologists exclude from this definition human-made solids such as concrete. With the term "solid," most geologists also exclude loose substances such as silt, clay, and sand from their definition of a rock. But sometimes it can be difficult to distinguish a loose material such as sand from a solid rock such as sandstone. To simplify matters, many geologists follow a simple rule: if you need a hammer to break it, it is a rock. This is not to say that rocks always remain in a solid state. Under great pressure, rocks can melt. Indeed, natural glass—a common type of rock—is formed by supercooling molten rock, or magma. Most rocks consist of a mixture of more than one substance, usually a variety of minerals and organic substances. Coal, for example, typically contains fragments of ancient plant debris, called macerals, mixed with assorted mineral grains. Most volcanic rocks contain a mixture of mineral grains and glass. Sometimes particles of a single mineral form the bulk of a rock, as calcite does in limestone. Rocks form the outer layer, or crust, of Earth. The rocks that can be seen on the surface or reached by digging through the soil are called bedrock. Over the centuries, geologists have mapped the bedrock of regions large and small. They have found that rocks of similar types underlie many large regions of the world. From these, geologists have developed three basic categories of rock, distinguished by the processes that form them. Igneous rock forms when molten rock below Earth's surface cools enough to solidify. The crust of the primitive Earth is believed to have once consisted entirely of igneous rock. Sedimentary rock, as its name implies, consists of sediment—particles of dissolved and weathered rock, as well as the remains of decayed plants and animals. Typically, sedimentary rock forms when such particles collect in oceans, lake beds, and other places, where they become cemented together in layers over hundreds or thousands of years. Metamorphic rock forms when preexisting rock sinks, without melting, deep into Earth, where it is twisted and deformed or chemically changed by heat, pressure, or chemicals. The processes that can transform one type of rock into another comprise the rock cycle. Traditionally the cycle is said to begin with igneous rock, which is weathered to sedimentary rock, and then transformed into metamorphic rock. But shortcuts in this cycle often occur. For example, a metamorphic rock may be weathered away to sediment without passing through the igneous stage. Similarly, igneous rock deep in the ground may be deformed into metamorphic rock without passing through the sedimentary stage. Igneous Rock. As magma cools, the elements flowing wi

In which part of the atmosphere is the ozone layer?

The Ozone Layer The ozone layer is a layer in Earth's atmosphere which contains relatively high concentrations of ozone (O3). This layer absorbs 97-99% of the sun's high frequency ultraviolet light, which is potentially damaging to life on earth. Over 90% of ozone in earth's atmosphere is present here "Relatively high" means a few parts per million—much higher than the concentrations in the lower atmosphere but still small compared to the main components of the atmosphere. It is mainly located in the lower portion of the stratosphere from approximately 15 km to 35 km above Earth's surface, though the thickness varies seasonally and geographically. A dobson unit is the most basic measure used in ozone research.One Dobson Unit (DU) is defined to be 0.01 mm thickness at STP (standard temperature and pressure). Ozone layer thickness is expressed in terms of Dobson units, which measure what its physical thickness would be if compressed in the Earth's atmosphere. In those terms, it's very thin indeed. A normal range is 300 to 500 Dobson units, which translates to an eighth of an inch-basically two stacked pennies.      In space, it's best not to envision the ozone layer as a distinct, measurable band. Instead, think of it in terms of parts per million concentrations in the stratosphere (the layer six to 30 miles above the Earth's surface). The unit is named after G.M.B. Dobson, one of the first scientists to investigate atmospheric ozone . A thinning ozone layer leads to a number of serious health risks for humans. It causes greater incidences of skin cancer and cataract of the eye, with children being particularly vulnerable. There are also serious impacts for biodiversity. Increased UV-B rays reduce levels of plankton in the oceans and subsequently diminish fish stocks. It can also have adverse effects on plant growth, thus reducing agricultural productivity. Another negative effect is the reduced lifespan of certain materials. Severe depletion of the Antarctic ozone layer was first observed in the early 1980s. The international response embodied in the Montreal Protocol. Today 191 countries worldwide have signed the Montreal Protocol which is widely regarded as the most successful Multinational Environmental Agreement ever reached to date. Furthermore the phasing out of ozone depleting substances (ODS) has helped to fight climate change since many ODS are also powerful greenhouse gases.

Which Indian state is at the eastern end of the Himalayas?

Indian Himalayan States - ENVIS on Himalayan Ecology, GBPIHED, Almora Indian Himalayan States % share of geographical area in the  Indian Himalayan Region (IHR) 1 JAMMU & KASHMIR Jammu & Kashmir, located in the extreme north of the country, is situated between 320 17' and 370 5' N latitudes and 720 40' and 800 30' E longitudes. It is bounded on north by China, on east by Tibet, on south by Himachal Pradesh and Punjab and on west by Pakistan. Geographically, this state is divided into four zones � the mountainous and semi-mountainous plain known as Kandi belt, hills including Siwalik ranges, mountains of Kashmir valley and Pir Panjal range, and Tibetan tract of Ladakh and Kargil. The state has a number of lakes, rivers, rivulets and glacial regions. The important rivers of this state are Indus, Chenab and Sutlej (Jhelum). There are extreme variations in climate in the state due to its location and topography. The climate of the state varies from tropical in Jammu plains to semi-arctic cold in Ladakh with Kashmir and Jammu mountainous tracts having temperate climatic conditions. The temperature of this state varies spatially. Leh is coldest and Jammu is the hottest region in the state. In the winter nights, temperature goes down below zero and very often heavy snowfall occurs during November to February. The annual rainfall varies from region to region with 92.6 mm in Leh, 650.5 mm in Srinagar and 1,115.9 mm in Jammu. Geologically, the state represents constituted rocks varying from the oldest period of the earth�s history to the youngest present day river and lake deposits.   Jammu & Kashmir at a glance Geographical area (km2) Agriculture (80% of total occupation) Major industries Handicrafts & handlooms *Included 78,114 and 37,555 km2 occupied by Pakistan and China, respectively, and 5,180 km2 handed over by Pakistan to China #Provisional figure of 2002 from SRS, Office of the Registrar General of India, Ministry of Home Affairs. HIMACHAL PRADESH Himachal Pradesh lies between the latitudes 30o 23' � 33 o 13' N and longitudes 75 o 43' -79 o 4' E. The state is bounded by Uttarakhand on the southeast, Tibet on the east, Punjab on the west and southwest, Haryana on south and Jammu & Kashmir on the north. It is situated in the northwest corner of the India; right in the lap of Himalayan ranges. The altitudinal variation ranges between 460 meters to 6,600 meters above mean sea level. The state is divided into three zones � the Siwaliks or the outer Himalaya, the low mountains which have less altitude in comparison to great mountains in the middle, and the zone of the Zanskar (high peaks of Himalaya). Many parts of this state are snow bound from December to April. Numerous passes and glaciers are found in this state. Most important rivers of this state are � Chenab (Chandrabhaga), Ravi (Iravati), Sutlej (Shatadru), Beas (Vipasa) and Yamuna (Jamuna). The Chenab flows 122 km inside Himachal Pradesh before it enters Jammu & Kashmir. Yamuna has a catchments area of 2,320 km2 in Himachal Pradesh. The climate of northern part or the glacial region of this state is almost cool throughout the year.  In winter, snowfall continues until March and could be as high as three meters on the average. The southern part has similarity with the plains and varies from hot to sub-humid. The state experiences cold season from October to middle of March, hot seasons from April to June, and rainy season begins from July and goes upto September.   Himachal Pradesh at a glance Geographical Area                   #Provisional figure of 2002 from SRS, Office of the Registrar General of India, Ministry of Home Affairs.    UTTARAKHAND            Uttarakhand is located between 28o 43' � 31o 27' N latitudes and 77o 34' � 81o 02' E longitudes. The river Tons separates the state from Himachal Pradesh in the north-west, whereas the river Kali separates it from Nepal in the east. The greater Himalaya is the northern boundary of the state and is also the international boarder with China (Tibet). Foot-hills

What is the name of the atmospheric gas which screens out the sun's harmful ultraviolet radiation?

Ultraviolet Radiation: How It Affects Life on Earth : Feature Articles   By Jeannie Allen · September 6, 2001 The sun radiates energy in a wide range of wavelengths, most of which are invisible to human eyes. The shorter the wavelength, the more energetic the radiation, and the greater the potential for harm. Ultraviolet (UV) radiation that reaches the Earth’s surface is in wavelengths between 290 and 400 nm (nanometers, or billionths of a meter). This is shorter than wavelengths of visible light, which are 400 to 700 nm. People and plants live with both helpful and harmful effects of ultraviolet (UV) radiation from the sun. (Photograph courtesy Jeannie Allen) UV radiation from the sun has always played important roles in our environment, and affects nearly all living organisms. Biological actions of many kinds have evolved to deal with it. Yet UV radiation at different wavelengths differs in its effects, and we have to live with the harmful effects as well as the helpful ones. Radiation at the longer UV wavelengths of 320-400 nm, called UV-A, plays a helpful and essential role in formation of Vitamin D by the skin, and plays a harmful role in that it causes sunburn on human skin and cataracts in our eyes. The incoming radiation at shorter wavelengths, 290-320 nm, falls within the UV-B part of the electromagnetic spectrum. (UV-B includes light with wavelengths down to 280 nm, but little to no radiation below 290 nm reaches the Earth’s surface). UV-B causes damage at the molecular level to the fundamental building block of life— deoxyribonucleic acid (DNA). Electromagnetic radiation exists in a range of wavelengths, which are delineated into major divisions for our convenience. Ultraviolet B radiation, harmful to living organisms, represents a small portion of the spectrum, from 290 to 320 nanometer wavelengths. (Illustration by Robert Simmon) DNA readily absorbs UV-B radiation, which commonly changes the shape of the molecule in one of several ways. The illustration below illustrates one such change in shape due to exposure to UV-B radiation. Changes in the DNA molecule often mean that protein-building enzymes cannot “read” the DNA code at that point on the molecule. As a result, distorted proteins can be made, or cells can die. Ultraviolet (UV) photons harm the DNA molecules of living organisms in different ways. In one common damage event, adjacent bases bond with each other, instead of across the “ladder.” This makes a bulge, and the distorted DNA molecule does not function properly. (Illustration by David Herring) But living cells are “smart.” Over millions of years of evolving in the presence of UV-B radiation, cells have developed the ability to repair DNA. A special enzyme arrives at the damage site, removes the damaged section of DNA, and replaces it with the proper components (based on information elsewhere on the DNA molecule). This makes DNA somewhat resilient to damage by UV-B. In addition to their own resiliency, living things and the cells they are made of are protected from excessive amounts of UV radiation by a chemical called ozone. A layer of ozone in the upper atmosphere absorbs UV radiation and prevents most of it from reaching the Earth. Yet since the mid-1970s, human activities have been changing the chemistry of the atmosphere in a way that reduces the amount of ozone in the stratosphere (the layer of atmosphere ranging from about 11 to 50 km in altitude). This means that more ultraviolet radiation can pass through the atmosphere to the Earth’s surface, particularly at the poles and nearby regions during certain times of the year. Without the layer of ozone in the stratosphere to protect us from excessive amounts of UV-B radiation, life as we know it would not exist. Scientific concern over ozone depletion in the upper atmosphere has prompted extensive efforts to assess the potential damage to life on Earth due to increased levels of UV-B radiation. Some effects have been studied, but much remains to be learned.

What is the world's deepest ocean?

Deepest Oceans and Seas of the World - Worldatlas.com Pacific Ocean (35,837 ft) (10,924 meters) Atlantic Ocean (30,246 ft) (9,219 meters) Indian Ocean (24,460 ft) (7,455 meters) Southern Ocean (23,737 ft) (7,236 meters) Caribbean Sea (22,788 ft) (6,946 meters) Arctic Ocean (18,456 ft) (5,625 meters) South China Sea (16,456 ft) (5,016 meters) Bering Sea (15,659 ft) (4,773 meters) Mediterranean Sea (15,197 ft) (4,632 meters) Gulf of Mexico (12,425 ft) (3,787 meters)

Which is the largest animal ever to have inhabited the Earth?

What is the biggest animal ever to exist on Earth? | HowStuffWorks What is the biggest animal ever to exist on Earth? Sebastien Burel/ Dreamstime.com By considerable measure, the largest known animal on Earth is the blue whale . Mature blue whales can measure anywhere from 75 feet (23 m) to 100 feet (30.5 m) from head to tail, and can weigh as much as 150 tons (136 metric tons). That's as long as an 8- to 10-story building and as heavy as about 112 adult male giraffes! These days, most adult blue whales are only 75 to 80 feet long; whalers hunted down most of the super giants. Female blue whales generally weigh more than the males. The largest blue whale to date is a female that weighed 389,760 pounds (176,792 kg). A blue whale's head is so wide that an entire professional football team -- about 50 people -- could stand on its tongue. Its heart is as big as a small car , and its arteries are wide enough that you could climb through them. Even baby blue whales dwarf most animals. At birth, a blue whale calf is about 25 feet (7.6 m) long and weighs more than an elephant. And they do grow up fast: During the first 7 months of its life, a blue whale drinks approximately 100 gallons (379 liters) of its mother's milk per day, putting on as much as 200 pounds (91 kg) every 24 hours. An adult blue whale can eat more than 4 tons (3.6 metric tons) of krill, a tiny shrimp-like creature, every day. A Whale of a World Marine Mammal Quiz This puts blue whales well above any known land mammal in terms of size. Most people believe that the largest animals to ever exist on Earth were the dinosaurs . However, one of the largest land dinosaurs, the sauropod Argentinosaurus, weighed only about 180,000 pounds (81,647 kg). That's little more than half the size of an adult blue whale. It makes a lot of sense that the world's largest animal would be a sea creature. Land animals have to support their own weight, whereas sea creatures get some help from the water. It is believed that at one time there were more than 200,000 blue whales. There are only about 10,000 blue whales now -- they've been on the endangered list since the mid-1960s -- and the population is not expected to recover. ­

What once covered 14% of the Earth's land area, but by 1991 over half had been destroyed?

deforestation CONTACT US DEFORESTATION Rainforests once covered 14% of the earth's land surface; now they cover a mere 6% and experts estimate that the last remaining rainforests could be consumed in less than 40 years.  Deforestation accounts for about 20% of global emissions of CO2 December 2015: Three trillion trees on planet Earth – what it means.  link Full article below in first section.   Google has developed an interactive map to show forest change around the planet.   link             ______________________________________________________________  Latest news: Nov. 24 2016: Protected forests in Europe felled to meet EU renewable targets. Protected forests are being indiscriminately felled across Europe to meet the EU’s renewable energy targets, according to an investigation by the conservation group Birdlife. Up to 65% of Europe’s renewable output currently comes from bioenergy, involving fuels such as wood pellets and chips, rather than wind and solar power. Bioenergy fuel is supposed to be harvested from residue such as forest waste but, under current legislation, European bioenergy plants do not have to produce evidence that their wood products have been sustainably sourced. In Slovakia, the drive to reach the EU’s renewable energy targets has seen a 72% increase in the use of wood for bioenergy since 2007, according to Birdlife . link         link The scale of deforestation - link Dec. 7 2015: Three trillion trees on planet Earth – what it means. A Yale University science team came to an estimate for the number of trees on Planet Earth - 3,041,000,000,000 - saying it is interesting to know the number of trees in the world but asking why is it useful? It is our duty as scientists to help environmental stewards and decision-makers by filling critical gaps in our knowledge. In the face of climate change - one of the most significant global threats to life as we know it – we are faced with one clear challenge: we must remove carbon from the atmosphere. Despite all of our best technological advances, it is nature that provides us with our single most effective weapons in this fight against rising CO2 concentrations. Trees absorb carbon directly from the atmosphere to be stored in their biomass and the soil. The United Nations Environment Programme ( Unep ) and  Plant for the Planet  designed the ambitious "Billion Tree Campaign". The problem was that no-one had any idea how many trees there were to start with. Without a baseline understanding of the Earth's forests, it was difficult to comprehend the impacts of these restoration efforts. By using strict criteria for the information that we include (e.g. using only trees with trunks equal to or larger than 10 cm diameter), and incorporating a huge amount of data into our predictive equations, the margin of error around this global estimate was exceptionally small (192 billion trees). By combining satellite technology with ground-sourced information collected by local forestry experts around the world, the most detailed map of the world's forests to date was generated. It revealed that the Earth's forests are home to approximately 3.041 trillion trees. Therefore one billion additional trees would only represent an increase of 0.03% on top of the current global number. In addition, the study revealed that we lose approximately 10 billion trees each year, so even if the billion tree campaign was repeated annually, it would not get us much closer to the goal of halting the net global forest loss. With new information, UNEP and Plant for the Planet’s new target is to restore one trillion trees, and work has begun in earnest - the total number of trees planted to date already exceeds 14 billion. link October 2015: Indonesia has the world's highest rate of deforestation, even higher than Brazil, which contains most of the Amazon rainforest. From 2000 to 2012, according to research published in  Nature , Indonesia lost more than 23,000 square miles of forest to logging, agriculture, and other uses. That's roughly the size of West Virginia. In 2010, the government attemp

Which inland sea between Kazakhstan and Uzbekistan is fast disappearing because the rivers that feed it have been diverted and dammed?

Effective Communication at Pepsi Co - Term Paper Effective Communication at Pepsi Co Which Indian state is at the eastern end of the Himalayas? A: Assam. What is the name of the atmospheric gas which screens out the sun's harmful ultraviolet radiation? A: Ozone. What is the world's deepest ocean? A: Pacific. Which is the largest animal ever to have inhabited the Earth? A: Blue Whale. What once covered 14% of the Earth's land area, but by 1991 over half had been destroyed? A: Rainforest. Which inland sea between Kazakhstan and Uzbekistan is fast disappearing because the rivers that feed it have been diverted and dammed? A: Aral Sea. The damaged Chernobyl nuclear power station is situated in which country? A: Ukraine. What type of rock is granite? A: Igneous. What type of rock is basalt? A: Igneous. What is the main constituent of natural gas? A: Methane. What is the term for nutrient enrichment of lakes? A: Eutrophication. Which of the Earth's atmospheric layers reflects radio waves? A: Ionosphere. Which gas forms 80% of Earth's atmosphere? A: Nitrogen. In which mountain chain would you find Mount Everest? A: Himalayas. What is the collective term for substances such as coal, oil and natural gas, the burning of which produces carbon dioxide? A: Fossil fuel. What contributes to the greenhouse effect at lower atmospheric levels, but in the upper atmosphere protects life on Earth? A: Ozone. What is the name of the process by which substances are washed out of the soil? A: Leaching. Who was director of the environmental pressure group Friends of the Earth 1984 - 90? A: Jonathon Porritt. Which European country is committed to decommissioning all of its nuclear reactors? A: Sweden. Which Canadian city gave its name to the 1987world agreement on protection of the ozone layer? A: Montreal. Five-legged creatures have damaged which 1250 mile long wonder of the world? A: Great Barrier Reef.

The damaged Chernobyl nuclear power station is situated in which country?

What is Chernobyl? | The Chernobyl Gallery Chernobyl in 2010 What is the Chernobyl Disaster? The Chernobyl nuclear disaster began early in the early hours of Saturday 26 April 1986 within the Chernobyl Nuclear Power Plant. An explosion and fire released large quantities of radioactive contamination into the atmosphere, which spread over much of Western USSR and Europe. It is considered the worst nuclear power plant accident in history and is one of only two classified as a level 7 event on the International Nuclear Event Scale (the other being the Fukushima nuclear disaster in 2011).   Aerial view of Reactor Four The disaster began during a systems test at reactor number four of the Chernobyl plant. There was a sudden surge of power output, and when an emergency shutdown was attempted a more extreme spike in power output occurred, which led a reactor vessel to rupture and a series of explosions. These events exposed the graphite moderator of the reactor to air, causing it to ignite. The resulting fire sent a plume of highly radioactive smoke into the atmosphere and over an extensive geographical area. The plume went on to drift over large parts of the western Soviet Union and Europe. According to official post-Soviet data about 60% of the radioactive fallout landed in Belarus.   Increased radiation dose across Europe The battle to contain the contamination and avert a greater catastrophe ultimately involved over 500,000 workers, known as liquidators ,  and cost an estimated 18 billion Rubles. Only after the level of radiation set off alarms at the Forsmark Nuclear Power Plant in Sweden, over one thousand kilometers from the Chernobyl Plant, did the Soviet Union publicly admit that an accident had occurred. The true scale of the disaster was concealed. After evacuating the nearby city of Pripyat, the following warning message was read on state TV:   “There has been an accident at the Chernobyl Nuclear Power Plant. One of the nuclear reactors was damaged. The effects of the accident are being remedied. Assistance has been provided to any affected people. An investigative commission has been set up.” – 28 April 1986, 21:00     From 1986 to 2000, over 350,000 people were evacuated and resettled from the most severely contaminated areas of Belarus, Russia, and Ukraine. Thirty one deaths are directly attributed to the accident, all among the reactor staff and emergency workers. Estimates of the number of deaths potentially resulting from the accident vary enormously. A UNSCEAR report places the total confirmed deaths from radiation at 64 as of 2008. The World Health Organization (WHO) suggests it could reach 4,000 civilian deaths, a figure which does not include military clean-up worker casualties. A 2006 report predicted 30,000 to 60,000 cancer deaths as a result of Chernobyl fallout. A Greenpeace report puts this figure at 200,000 or more. The Russian publication, Chernobyl, concludes that 985,000 premature cancer deaths occurred worldwide between 1986 and 2004 as a result of radioactive contamination from Chernobyl.   “Nearly 400 million people resided in territories that were contaminated with radioactivity at a level higher than 4 kBq/m2 (0.11 Ci/km2) from April to July 1986. Nearly 5 million people (including, more than 1 million children) still live with dangerous levels of radioactive contamination in Belarus, Ukraine, and European Russia.” Chernobyl: Consequences of the Catastrophe for People and the Environment (PDF; 4,3 MB) 2009   A massive concrete and metal structure, a sarcophagus , was hastily constructed to encase Unit 4 as an emergency measure to halt the release of radiation into the atmosphere following the 1986 disaster.   What is the Exclusion Zone? The “Chernobyl Nuclear Power Plant Zone of Alienation” is the officially designated exclusion area around the site of the Chernobyl nuclear reactor disaster. It is commonly known as the “Chernobyl Exclusion Zone” or simply “The Zone”. Established soon after the disaster by the Russian military to cover the areas worst affected by radioactive contamination it wa

What type of rock is granite?

Granite - Igneous Rock Types Igneous Rock Types Pictures of Igneous Rock Types Use Deep Earth and Other Planets Granite consists of quartz (gray), plagioclase feldspar (white) and alkali feldspar (beige) plus dark minerals, in this case biotite and hornblende . (more below) "Granite" is used by the public as a catch-all name for any light-colored, coarse-grained igneous rock. The geologist examines these in the field and calls them granitoids pending laboratory tests. The key to true granite is that it contains sizable amounts of quartz and both kinds of feldspar. This article goes much deeper into granite . This granite specimen comes from the Salinian block of central California, a chunk of ancient crust carried up from southern California along the San Andreas fault. Pictures of other granite specimens appear in the granite picture gallery . Also see the granite landforms of Joshua Tree National Park . And big closeup pictures of granite are available in the closeup rock wallpaper photos . Photo Credit: Photo (c) 2004 Andrew Alden, licensed to About.com ( fair use policy )

What type of rock is basalt?

Basalt: Igneous Rock - Pictures, Definition, Uses & More Basalt What Is Basalt, How Does It Form, and How Is It Used? Basalt: A fine-grained igneous rock that is usually black in color. The specimen shown is about two inches (five centimeters) across. What is Basalt? Basalt is a dark-colored, fine-grained, igneous rock composed mainly of plagioclase and pyroxene minerals. It most commonly forms as an extrusive rock, such as a lava flow, but can also form in small intrusive bodies, such as an igneous dike or a thin sill. It has a composition similar to gabbro . The difference between basalt and gabbro is that basalt is a fine-grained rock while gabbro is a coarse-grained rock. Olympus Mons Volcano: This shield volcano is composed of basalt and has enormous calderas at the summit. Olympus Mons is the highest topographic feature on Mars and is the largest known volcano in our solar system. It is about 375 miles (600 kilometers) in diameter and 15 miles (25 kilometers) high. NASA Mars Orbiter Camera image. Earth's Most Abundant Bedrock Basalt underlies more of Earth's surface than any other rock type. Most areas within Earth's ocean basins are underlain by basalt. Although basalt is much less common on continents, lava flows and flood basalts underlie several percent of Earth's land surface. Basalt is a very important rock. Basalt on Moon and Mars Basalt is also an abundant rock on the Moon. Much of the Moon's surface is underlain by basaltic lava flows and flood basalts. These areas of the Moon are known as "lunar maria." Large areas of the Moon have been resurfaced by extensive basalt flows which may have been triggered by major impact events. The ages of lunar maria can be estimated by observing the density of impact craters on their surface. Younger basalt flows will have fewer craters. Olympus Mons is a shield volcano on Mars. It, like most other volcanic features on Mars, was formed from basaltic lava flows. It is the highest mountain on Mars and is the largest known volcano in our solar system. Basalt-Forming Environments: This map shows the location of oceanic divergent boundaries and hotspots. These are locations where large volumes of basalt have been formed. Map copyright by Geology.com and MapResources. Locations generalized after United States Geological Survey, Geologic Investigations Map I-2800: This Dynamic Planet. Igneous rock composition chart: This chart shows that basalt is typically composed of pyroxenes, plagioclase, micas, and amphiboles. Basalt-Forming Environments Most of the basalt found on Earth was produced in just three rock-forming environments: 1) oceanic divergent boundaries , 2) oceanic hotspots , and 3) mantle plumes and hotspots beneath continents . The images on this page feature some of these basalt-forming environments. Sea floor pillow basalts on the Juan de Fuca Ridge, a divergent plate boundary located about 150 miles (240 kilometers) west of the Washington-Oregon coast. This lava flow, produced by a fissure eruption, was about five years old when the photograph was taken. NOAA Ocean Explorer image. Hawaii Basalt Flows: Lava flows dump into the Pacific Ocean on the coast of Hawaii. Multiple locations where hot lava streams into the ocean can be seen in this image along with a red-hot lava flow traversing the lava field. This photo shows the enormous extent of the flows. They extend from the shoreline up to the horizon. A volcanic plume from the Pu`u `O`o vent can be seen over the horizon near the center of the image. The lava in these flows originated from the Pu`u `O`o vent. USGS image. Basalts at Oceanic Divergent Boundaries Most of Earth's basalt is produced at divergent plate boundaries on the mid-ocean ridge system (see map). Here convection currents deliver hot rock from deep in the mantle. This hot rock melts as the divergent boundary pulls apart, and the molten rock erupts onto the sea floor. These submarine fissure eruptions often produce pillow basalts as shown in the image on this page. The active mid-ocean ridges host repeated fissure eruptions.

What is the main constituent of natural gas?

Components of Natural Gas - Enbridge Gas Distribution Components of Natural Gas Components of Natural Gas Properties of Natural Gas Natural gas is a colourless, tasteless, odourless, and non-toxic gas. Because it is odourless, mercaptan is added to the natural gas, in very small amounts to give the gas a distinctive smell of rotten eggs. This strong smell can alert you of a potential gas leak . Natural gas is about 40 per cent lighter than air, it has a high ignition temperature and a narrow flammability range, meaning natural gas will ignite at temperatures above 1,000 degrees and burn at a mix of approximately 4-15 per cent volume in air. For more information on natural gas, visit the  Canadian Gas Association . To learn more about the physical properties of natural gas, download our Material Safety Data Sheet (MSDS): Fiche technique pour le gaz naturel Chemical Composition of Natural Gas Natural gas is primarily composed of methane, but also contains ethane, propane and heavier hydrocarbons. It also contains small amounts of nitrogen, carbon dioxide, hydrogen sulphide and trace amounts of water. The monthly average chemical compositions of natural gas for Victoria Square, which supplies the Greater Toronto Area, are provided below:

Which of the Earth's atmospheric layers reflects radio waves?

The Atmosphere and Radio Waves | Ionosphere The Atmosphere and Radio Waves View More The atmosphere plays a vital role in the way in which radio waves travel around the earth. Without its action it would not be possible for signals to travel around the globe on the short wave bands, or travel greater than only the line of sight distance at higher frequencies. with an interest in the topic. Copyright: Attribution Non-Commercial (BY-NC)   THE ATMOSPHERE AND RADIO WAVES The atmosphere plays a vital role in the way in which radio waves travel around the earth.Without its action it would not be possible for signals to travel around the globe on the shortwave bands, or travel greater than only the line of sight distance at higher frequencies. Infact the way in which the atmosphere affects radio is of tremendous importance for anyonewith an interest in the topic.In view of the importance of the atmosphere an overview of its make-up is given here. Layers of the Atmosphere The atmosphere can be split up into a variety of different layers according to their properties. As different aspects of science look at different properties there is no singlenomenclature for the layers. The system that is most widely used is that associated with.Lowest is the troposphere that extends to a height of 10 km. Above this at altitudesbetween 10 and 50 km is found the stratosphere. This contains the ozone layer at a heightof around 20 km. Above the stratosphere, there is the mesosphere extending from analtitude of 50 km to 80 km, and above this is the thermosphere whereThere are two main layers that are of interest from a radio viewpoint. The first is thetroposphere that tends to affect frequencies above 30 MHz. The second is the ionosphere.This a region which crosses over the boundaries of the meteorological layers and extendsfrom around 60 km up to 700 km. Here the air becomes ionised, producing ions and freeelectrons. The free electrons affect radio waves at certain frequencies, often bending themback to earth so that they can be heard over vast distances around the world.     Troposphere The lowest of the layers of the atmosphere is the troposphere. This extends from groundlevel to an altitude of 10 km. It is within this region that the effects that govern our weather occur. To give an idea of the altitudes involved it is found that low clouds occur at altitudesof up to 2 km whereas medium level clouds extend to about 4 km. The highest clouds arefound at altitudes up to 10 km whereas modern jet airliners fly above this at altitudes of upto 15 km.Within the troposphere there is generally a steady fall in temperature with height and thishas a distinct bearing on some propagation modes which occur in this region. The fall intemperature continues in the troposphere until the tropopause is reached. This is the areawhere the temperature gradient levels out and then the temperature starts to rise. At thispoint the temperature is around -50 ºC.The refractive index of the air in the troposphere plays a dominant role in radio signalpropagation. This depends on the temperature, pressure and humidity. When radio signalsare affected this often occurs at altitudes up to 2 km. The ionosphere The ionosphere is an area where there is a very high level of free electrons and ions. It isfound that the free electrons affect radio waves. Although there are low levels of ions andelectrons at all altitudes, the number starts to rise noticeably at an altitude of around 30 km.However it is not until an altitude of approximately 60 km is reached that the it rises to asufficient degree to have a major effect on radio signals.The overall way in which the ionosphere is very complicated. It involves radiation from thesun striking the molecules in the upper atmosphere. This radiation is sufficiently intensethat when it strikes the gas molecules some electrons are given sufficient energy to leavethe molecular structure. This leaves a molecule with a deficit of one electron that is calledan ion, and a free electron. As might be expected the most common molecules to beionised ar

Which gas forms 80% of Earth's atmosphere?

Introduction to the Atmosphere: Background Material Introduction to the Atmosphere This section provides a brief overview of the properties associated with the atmosphere. The general concepts found in this section are: The earth's atmosphere is a very thin layer wrapped around a very large planet. Two gases make up the bulk of the earth's atmosphere: nitrogen ( ), which comprises 78% of the atmosphere, and oxygen ( ), which accounts for 21%. Various trace gases make up the remainder. Based on temperature, the atmosphere is divided into four layers: the troposphere, stratosphere, mesosphere, and thermosphere. Energy is transferred between the earth's surface and the atmosphere via conduction, convection, and radiation. Ocean currents play a significant role in transferring this heat poleward. Major currents, such as the northward flowing Gulf Stream, transport tremendous amounts of heat poleward and contribute to the development of many types of weather phenomena. This section includes seven classroom activities. Atmospheric Properties The thin envelope of air that surrounds our planet is a mixture of gases, each with its own physical properties. The mixture is far from evenly divided. Two elements, nitrogen and oxygen, make up 99% of the volume of air. The other 1% is composed of "trace" gases, the most prevalent of which is the inert gaseous element argon. The rest of the trace gases, although present in only minute amounts, are very important to life on earth. Two in particular, carbon dioxide and ozone, can have a large impact on atmospheric processes. Another gas, water vapor, also exists in small amounts. It varies in concentration from being almost non-existent over desert regions to about 4% over the oceans. Water vapor is important to weather production since it exists in gaseous, liquid, and solid phases and absorbs radiant energy from the earth. Structure of the Atmosphere The atmosphere is divided vertically into four layers based on temperature: the troposphere, stratosphere, mesosphere, and thermosphere. Throughout the Cycles unit, we'll focus primarily on the layer in which we live - the troposphere. Troposphere The word troposphere comes from tropein, meaning to turn or change. All of the earth's weather occurs in the troposphere. The troposphere has the following characteristics. It extends from the earth's surface to an average of 12 km (7 miles). The pressure ranges from 1000 to 200 millibars (29.92 in. to 5.92 in.). The temperature generally decreases with increasing height up to the tropopause (top of the troposphere); this is near 200 millibars or 36,000 ft. The temperature averages 15°C (59°F) near the surface and -57°C (-71°F) at the tropopause. The layer ends at the point where temperature no longer varies with height. This area, known as the tropopause, marks the transition to the stratosphere. Winds increase with height up to the jet stream. The moisture concentration decreases with height up to the tropopause. The air is much drier above the tropopause, in the stratosphere. The sun's heat that warms the earth's surface is transported upwards largely by convection and is mixed by updrafts and downdrafts. The troposphere is 70% Atmospheric Processes Interactions - Atmosphere and Ocean In the Cycles overview, we learned that water is an essential part of the earth's system. The oceans cover nearly three-quarters of the earth's surface and play an important role in exchanging and transporting heat and moisture in the atmosphere. Most of the water vapor in the atmosphere comes from the oceans. Most of the precipitation falling over land finds its way back to oceans. About two-thirds returns to the atmosphere via the water cycle. You may have figured out by now that the oceans and atmosphere interact extensively. Oceans not only act as an abundant moisture source for

In which mountain chain would you find Mount Everest?

Mountains, Mountain Range Information, Facts, News, Photos -- National Geographic Space Photograph by George Mobley Mountains are the wrinkles of age and pimples of youth on Earth's crusty outer skin. They rise up as the crust collides, cracks, crumbles, folds, and spews. By definition, they dominate their surroundings with towering height. The mighty chunks rise all over the world, including the oceans. They usually have steep, sloping sides and sharp or rounded ridges. The highest point is called the peak or summit. Most geologists classify a mountain as a landform that rises at least 1,000 feet (300 meters) or more above its surrounding area. A mountain range is a series or chain of mountains that are close together. The world's tallest mountain ranges form when pieces of Earth's crust—called plates—smash against each other, in a process called plate tectonics, and buckle up like the hood of a car in a head-on collision. The Himalaya in Asia formed from one such massive wreck that started about 55 million years ago. Thirty of the world’s highest mountains are in the Himalaya. The summit of Mount Everest, at 29,035 feet (8,850 meters), is the highest point on Earth. The tallest mountain measured from top to bottom is Mauna Kea, an inactive volcano on the island of Hawaii in the Pacific Ocean. Measured from the base, Mauna Kea stands 33,474 feet (10,203 meters) tall, though it only rises 13,796 feet (4,205 meters) above the sea. Types of Mountains Volcanic mountains form when molten rock from deep inside the Earth erupts through the crust and piles up on itself. The island chain of Hawaii is actually the tops of volcanoes. Well-known volcanoes on land include Mount St. Helens in Washington State and Mount Fuji in Japan. Sometimes volcanic eruptions break down mountains instead of building them up, like the 1980 eruption that blew the top off Mount St. Helens. When magma pushes the crust up but hardens before erupting onto the surface, it forms so-called dome mountains. Wind and rain pummel the domes, sculpting peaks and valleys. Examples include the Black Hills of South Dakota and the Adirondack Mountains of New York. Plateau mountains are similar to dome mountains, but form as colliding tectonic plates push up the land without folding or faulting. They are then shaped by weathering and erosion. Other types of mountains form when stresses within and between the tectonic plates lead to cracking and faulting of the Earth's surface, which forces blocks of rock up and down. Examples of fault-block mountains include the Sierra Nevada in California and Nevada, the Tetons in Wyoming, and the Harz Mountains in Germany. Mountains often serve as geographic features that define natural borders of countries. Their height can influence weather patterns, stalling storms that roll off the oceans and squeezing water from the clouds. The other side is often much drier. The rugged landscapes even provide refuge—and protection—for fleeing and invading armies.

What is the collective term for substances such as coal, oil and natural gas, the burning of which produces carbon dioxide?

» Natural Gas and the Environment NaturalGas.org The Natural Gas Industry and the Environment Emissions from the Combustion of Natural Gas Natural gas is the cleanest of all the fossil fuels, as evidenced in the Environmental Protection Agency’s data comparisons in the chart below, which is still current as of 2010. Composed primarily of methane, the main products of the  combustion  of natural gas are carbon dioxide and water vapor, the same compounds we exhale when we breathe. Coal and oil are composed of much more complex molecules, with a higher carbon ratio and higher nitrogen and sulfur contents. This means that when combusted, coal and oil release higher levels of harmful emissions, including a higher ratio of carbon emissions, nitrogen oxides (NOx), and sulfur dioxide (SO2). Coal and fuel oil also release ash particles into the environment, substances that do not burn but instead are carried into the atmosphere and contribute to pollution. The combustion of natural gas, on the other hand, releases very small amounts of sulfur dioxide and nitrogen oxides, virtually no ash or particulate matter, and lower levels of carbon dioxide, carbon monoxide, and other reactive hydrocarbons. Fossil Fuel Emission Levels Source: EIA – Natural Gas Issues and Trends 1998   Natural gas, as the cleanest of the fossil fuels, can be used in many ways to help reduce the emissions of pollutants into the atmosphere. Burning natural gas in the place of other fossil fuels emits fewer harmful pollutants, and an increased reliance on natural gas can potentially reduce the emission of many of these most harmful pollutants. Pollutants emitted in the United States, particularly from the combustion of fossil fuels, have led to the development of many pressing environmental problems. Natural gas, emitting fewer harmful chemicals into the atmosphere than other fossil fuels, can help to mitigate some of these environmental issues. These issues include: Greenhouse Gas Emissions Source: Intergovernmental Panel on Climate Change-2007 Global warming, or the ‘greenhouse effect’ is an environmental issue that deals with the potential for global climate change due to increased levels of atmospheric ‘greenhouse gases’. There are certain gases in our atmosphere that serve to regulate the amount of heat that is kept close to the earth’s surface. Scientists theorize that an increase in these greenhouse gases will translate into increased temperatures around the globe, which would result in many disastrous environmental effects. In fact, the Intergovernmental Panel on Climate Change (IPCC) predicts in its ‘Fourth Assessment Report’ released in 2007 that during the 21st century, global average temperatures are expected to rise by between 2.0 and 11.5 degrees Fahrenheit.  A Fifth Assessment Report is expected to be released by the IPCC between 2013 and 2015. Power Plants Contribute to the Emission of Greenhouse Gases Source: API The principle greenhouse gases include water vapor, carbon dioxide, methane, nitrogen oxides, and some engineered chemicals such as cholorofluorocarbons. While most of these gases occur in the atmosphere naturally, levels have been increasing due to the widespread burning of fossil fuels by growing human populations. The reduction of greenhouse gas emissions has become a primary focus of environmental programs in countries around the world. One of the principle greenhouse gases is carbon dioxide. Although carbon dioxide does not trap heat as effectively as other greenhouse gases (making it a less potent greenhouse gas), the sheer volume of carbon dioxide emissions into the atmosphere is very high, particularly from the burning of fossil fuels. In fact, according to the Energy Information Administration in its December 2009 report ‘Emissions of Greenhouse Gases’ in the United States, 81.3 percent of greenhouse gas emissions in the United States in 2008 came from energy-related carbon dioxide. Source: EIA-Emissions of Greenhouse Gases Report 2009 Because carbon dioxide makes up such a high proportion of U.S. greenhouse gas emissions, reduc

What contributes to the greenhouse effect at lower atmospheric levels, but in the upper atmosphere protects life on Earth?

Climate Change: Vital Signs of the Planet: Causes Vital Signs of the Planet Questions (FAQ) A blanket around the Earth A layer of greenhouse gases – primarily water vapor, and including much smaller amounts of carbon dioxide, methane and nitrous oxide – acts as a thermal blanket for the Earth, absorbing heat and warming the surface to a life-supporting average of 59 degrees Fahrenheit (15 degrees Celsius). Most climate scientists agree the main cause of the current global warming trend is human expansion of the "greenhouse effect" 1 — warming that results when the atmosphere traps heat radiating from Earth toward space. Certain gases in the atmosphere block heat from escaping. Long-lived gases that remain semi-permanently in the atmosphere and do not respond physically or chemically to changes in temperature are described as "forcing" climate change. Gases, such as water vapor, which respond physically or chemically to changes in temperature are seen as "feedbacks." Gases that contribute to the greenhouse effect include: Water vapor. The most abundant greenhouse gas, but importantly, it acts as a feedback to the climate. Water vapor increases as the Earth's atmosphere warms, but so does the possibility of clouds and precipitation, making these some of the most important feedback mechanisms to the greenhouse effect. Carbon dioxide (CO2). A minor but very important component of the atmosphere, carbon dioxide is released through natural processes such as respiration and volcano eruptions and through human activities such as deforestation, land use changes, and burning fossil fuels. Humans have increased atmospheric CO2 concentration by more than a third since the Industrial Revolution began. This is the most important long-lived "forcing" of climate change. Methane. A hydrocarbon gas produced both through natural sources and human activities, including the decomposition of wastes in landfills, agriculture, and especially rice cultivation, as well as ruminant digestion and manure management associated with domestic livestock. On a molecule-for-molecule basis, methane is a far more active greenhouse gas than carbon dioxide, but also one which is much less abundant in the atmosphere. Nitrous oxide. A powerful greenhouse gas produced by soil cultivation practices, especially the use of commercial and organic fertilizers, fossil fuel combustion, nitric acid production, and biomass burning. Chlorofluorocarbons (CFCs). Synthetic compounds entirely of industrial origin used in a number of applications, but now largely regulated in production and release to the atmosphere by international agreement for their ability to contribute to destruction of the ozone layer. They are also greenhouse gases. Not enough greenhouse effect: The planet Mars has a very thin atmosphere, nearly all carbon dioxide. Because of the low atmospheric pressure, and with little to no methane or water vapor to reinforce the weak greenhouse effect, Mars has a largely frozen surface that shows no evidence of life. Too much greenhouse effect: The atmosphere of Venus, like Mars, is nearly all carbon dioxide. But Venus has about 300 times as much carbon dioxide in its atmosphere as Earth and Mars do, producing a runaway greenhouse effect and a surface temperature hot enough to melt lead. On Earth, human activities are changing the natural greenhouse. Over the last century the burning of fossil fuels like coal and oil has increased the concentration of atmospheric carbon dioxide (CO2). This happens because the coal or oil burning process combines carbon with oxygen in the air to make CO2. To a lesser extent, the clearing of land for agriculture, industry, and other human activities has increased concentrations of greenhouse gases. The consequences of changing the natural atmospheric greenhouse are difficult to predict, but certain effects seem likely: On average, Earth will become warmer. Some regions may welcome warmer temperatures, but others may not. Warmer conditions will probably lead to more evaporation and precipitation overall, but individual regio

What is the name of the process by which substances are washed out of the soil?

Ch02 Some countries poison soils Why should the leaders of countries today commit their governments and their people to the hard work and expense of a national programme of soil conservation? The answer is that soil takes many years to create, but it can be destroyed in almost no time at all. With the loss of soil goes man's ability to grow food crops and graze animals, to produce fibre and forests. It is not enough to describe the soil as a country's greatest source of wealth; it is more than that; it is a country's life. And in one country after another today, the soil is washing or blowing away.   Soil is a complex mixture Soil covers most of the land surface of the earth in a thin layer, ranging from a few centimetres to several metres deep. It is composed of rock and mineral particles of many sizes mixed with water, air, and living things, both plant and animal, and their remains. As man measures time, soil formation is extremely slow. Where the climate is moist and warm, it takes thousands of years to form just a few centimetres of soil. In cold or dry climates, it takes even longer, or soil may not form at all. While soil is technically a renewable resource, its slow rate of formation makes it practically irreplaceable. Soil is a dynamic mixture, forever changing as water comes and goes and plants and animals live and die. Wind, water, ice, and gravity move soil particles about, sometimes slowly, sometimes rapidly. But even though a soil changes, the layers of soil stay much the same during one human lifetime unless they are moved or scraped, or ploughed by man.   Soil teems with life All soil is full of life, and good soils are teeming with it. Plants and animals help keep the soil fertile. Plant roots tunnel through the soil and break it up, and decaying plants form humus. Burrowing animals mix the soil; the excrete of animals contribute nutrients and improve soil structure. Besides the soil's more obvious inhabitants, which include rodents, insects, mites, slugs and snails, spiders, and earthworms, there are countless microscopic residents, some helpful to man and his crops, some harmful. Good soils seem to hold the greatest populations of bacteria. Almost without exception, bacteria are involved in basic enzyme transformations that make possible the growth of higher plants, including our food crops. From man's point of view, bacteria may well be the most valuable of the life forms in soil. Chemical reactions occur in the soil as a result of exchange of positive ions, or cations. More exchanges take place in clay soils than in any other type. These chemical reactions are also essential to plant growth and development and are a good index of soil fertility.   Only a fraction of land is arable Man's chief interest in soil is for agriculture, but not all soils are suitable for farming. The total land area of the world exceeds 13 billion hectares, but less than half can be used for agriculture, including grazing. A much smaller fraction - about 1.4 billion hectares - is presently suitable for growing crops. The rest of the land is either too wet or too dry, too shallow or too rocky. Some is toxic or deficient in the nutrients that plants require and some is permanently frozen . Europe, Central America, and North America have the highest proportion of soils suitable for farming, although a number of the more developed countries seem intent on paving over much of their best farmland with roads and buildings. The lowest proportions of arable soils are in North and Central Asia, South America, and Australia. The single most serious drawback to farming additional land is lack of water.   Erosion destroyed civilizations Civilizations began where farming was most productive. When farm productivity declined, usually as a result of soil mismanagement, civilizations also declined - and occasionally vanished entirely. Of the three requisites for a thriving civilization: fertile soil, a dependable water supply and relatively level land with reasonable rainfall which would not cause erosion, it is likely that the third factor w

Who was director of the environmental pressure group Friends of the Earth 1984 - 90?

Our Board of Trustees | Forum for the Future Our Board of Trustees Keith Clarke CBE, Chair ​ Keith joined the board of Forum for the Future in 2011 and became chair in July 2012. He was formerly the chief executive of the global engineering and design consultancy, Atkins. Keith is a chartered architect with more than 40 years’ experience in construction and engineering. He is a non-executive director for Sirius Minerals plc, Chair of Future Cities Catapult and Tidal Lagoon Power plc, vice president of the Institute of Civil Engineers, patron of the Environmental Industries Commission at Oxford; and has Honorary Fellowships from the Royal Academy of Engineering, the Institution of Structural Engineers and Cardiff University.  He is also Visiting Professor for Sustainable Design at Aston University. Keith served as chairman of the UK Construction Industry Council (CIC) from 2008-10 after previously chairing its Health and Safety Committee.     Volker Beckers Volker has built up more than 20 years’ senior experience within the utility industry and has a comprehensive knowledge of European energy markets. He was Group CEO, RWE Npower plc until the end of 2012 and prior to this, its Group CFO from 2003 to 2009. He has worked in a variety of trade and industry bodies, including the CBI President’s Committee, on the Board of the German-British Chamber of Industry & Commerce, and since 1999 as Deputy Chair of the Executive Commercial Management Committee at the German Association of Energy and Water Industries (BDEW) and was also member of the Executive Committee of UKBCSE (now Energy UK). Since 2009 he chairs the Business Energy Forum.  Among various other non-Executive Directorships, Volker is currently non-executive Director, HM Revenue & Customs and Chair of its Scrutiny Committee. He also sits on the Advisory Board of the EU Centre for Energy and Resource Security (EUCERS) at King’s College and is Chair of the Advisory Board of Erasmus Centre for Future Energy Business at Rotterdam School of Management, Erasmus University.   ​Kelvyn Derrick OBE   Kelvyn has international business experience extending more than 40 years. Until 2007 he was the Chief Executive of Hamworthy plc , leading its transformation into an innovative technology company with international scope, and floating the company in 2004. Prior to that he was a founding partner of a private equity firm. In the past 15 years he has held many Non-Executive Director roles including Deputy Chair of the SW Regional Development Agency, Chair of the Society of Maritime Industries , Chair of Regen SW and a board member of the Bournemouth Symphony Orchestra . More recent roles include providing strategic advice to an innovative energy from waste group and trustee of Dorset Wildlife Trust . Kelvyn was awarded the OBE for services to engineering and international trade in the 2009 New Year’s Honours List.     ​Kate Levick Kate is head of government relations at the environmental charity CDP, leading work on regulatory engagement, public affairs and government fundraising in an international context. She previously worked at the UK Government Office of Climate Change helping to formulate domestic and international climate change policy, and at BP in a variety of commercial and environmental roles which included group environmental policy and strategy for low-carbon business in emerging markets. Kate has an MProf in Leadership for Sustainable Development from Forum for the Future.     Sara Parkin OBE Along with Jonathon Porritt and Paul Ekins, Sara is a founder of Forum for the Future for which she designed the Forum Masters in Leadership for Sustainable ​Development.  She taught the Masters for 20 years until 2016 when the University of Surrey University took it over, Forum deciding to develop a more flexible modular, international learning programme.  Together, the 250 graduates count as one of Forum for the Future’s greatest contribution to a sustainable future.   Sara’s 2010 book, based on the Forum Masters, The Positive Deviant: Sustainability Leadership in a Perverse Wor