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What causes the particles of medium to move parallel to the direction of the wave? | Sound waves. | mechanical waves | fluid waves | longitudinal waves | Longitudinal waves cause the particles of medium to move parallel to the direction of the wave. |
Which state of matter lacks a fixed volume, fixed shape, and consists of charged particles? | isotopes | electrons | atoms | ions | Plasma is a state of matter that lacks a fixed volume and a fixed shape and consists of charged particles called ions. Because it consists of charged particles, plasma can conduct electricity and respond to a magnetic field. |
What type of cell transmits electrical impulses in the nervous system? | trace cell | toxin cell | Large Cell | nerve cell | cell that transmits electrical impulses in the nervous system; commonly called nerve cell. |
What is the force pushing a rocket called? | direction | momentum | friction | thrust | Most halogens have a variety of important uses. A few are described in the Table below . |
In headwater streams, what plant process is mostly attributed to algae that are growing on rocks? | reproduction | mitosis | symbiosis | photosynthesis | Abiotic features of rivers and streams vary along the length of the river or stream. Streams begin at a point of origin referred to as source water. The source water is usually cold, low in nutrients, and clear. The channel (the width of the river or stream) is narrower here than at any other place along the length of the river or stream. Headwater streams are of necessity at a higher elevation than the mouth of the river and often originate in regions with steep grades leading to higher flow rates than lower elevation stretches of the river. Faster-moving water and the short distance from its origin results in minimal silt levels in headwater streams; therefore, the water is clear. Photosynthesis here is mostly attributed to algae that are growing on rocks; the swift current inhibits the growth of phytoplankton. Photosynthesis may be further reduced by tree cover reaching over the narrow stream. This shading also keeps temperatures lower. An additional input of energy can come from leaves or other organic material that falls into a river or stream from the trees and other plants that border the water. When the leaves decompose, the organic material and nutrients in the leaves are returned to the water. The leaves also support a food chain of invertebrates that eat them and are in turn eaten by predatory invertebrates and fish. Plants and animals have adapted to this fast-moving water. For instance, leeches (phylum Annelida) have elongated bodies and suckers on both ends. These suckers attach to the substrate, keeping the leech anchored in place. In temperate regions, freshwater trout species (phylum Chordata) may be an important predator in these fast-moving and colder river and streams. |
What is the term that refers to stored chemical energy in organic matter or wastes? | starch energy | nuclear energy | potential energy | biomass energy | The stored chemical energy in organic matter or wastes is called biomass energy. The organic matter may be trees or other plants, or it may be wastes from homes and industries. When biomass is burned, it produces thermal energy that can be used for heating homes, cooking, or generating electricity. Biomass—especially wood—is an important energy source in the poorer nations where most people can’t afford fossil fuels. However, burning biomass releases air pollution and contributes to global climate change. Biomass can be used to make ethanol, a fuel that is added to gasoline. Although ethanol releases less pollution than gasoline, large areas of land are needed to grow the plants needed to make it (see Figure below ). This reduces the amount of land available for food production. |
The process of photosynthesis ultimately gets powered by what kind of energy? | nonrenewable energy | biofuel | electricity | light | |
A binary molecular compound is a molecular compound that is composed of what? | four elements | two atoms | four atoms | two elements | A binary molecular compound is a molecular compound that is composed of two elements. In general, the elements that combine to form binary molecular compounds are both nonmetals. This contrasts with ionic compounds, which usually involve bonds between metal ions and nonmetal ions. Because ionic charges cannot be used to name these compounds or to write their formulas, a different naming system must be used for molecular compounds. Another difference between ionic and molecular compounds is that two nonmetal atoms will frequently combine with one another in a variety of ratios. For example, nitrogen and oxygen combine to make several binary compounds, including NO, NO 2 , and N 2 O. Obviously they can’t all be called nitrogen oxide! How would someone know which one you were talking about? Each of the three compounds has very different properties and reactivity. A system to distinguish between compounds such as these is necessary. |
Within the first 8 weeks of gestation, a developing embryo establishes the rudimentary structures of all of its organs and tissues from the ectoderm, mesoderm, and endoderm. this process is called what? | parthenogenesis | abiogenesis | biosynthesis | organogenesis | Within the first 8 weeks of gestation, a developing embryo establishes the rudimentary structures of all of its organs and tissues from the ectoderm, mesoderm, and endoderm. This process is called organogenesis. Like the central nervous system, the heart also begins its development in the embryo as a tube-like structure, connected via capillaries to the chorionic villi. Cells of the primitive tube-shaped heart are capable of electrical conduction and contraction. The heart begins beating in the beginning of the fourth week, although it does not actually pump embryonic blood until a week later, when the oversized liver has begun producing red blood cells. (This is a temporary responsibility of the embryonic liver that the bone marrow will assume during fetal development. ) During weeks 4–5, the eye pits form, limb buds become apparent, and the rudiments of the pulmonary system are formed. During the sixth week, uncontrolled fetal limb movements begin to occur. The gastrointestinal system develops too rapidly for the embryonic abdomen to accommodate it, and the intestines temporarily loop into the umbilical cord. Paddle-shaped hands and feet develop fingers and toes by the process of apoptosis (programmed cell death), which causes the tissues between the fingers to disintegrate. By week 7, the facial structure is more complex and includes nostrils, outer ears, and lenses (Figure 28.15). By the eighth week, the head is nearly as large as the rest of the embryo’s body, and all major brain structures are in place. The external genitalia are apparent, but at this point, male and female embryos are indistinguishable. Bone begins to replace cartilage in the embryonic skeleton through the process of ossification. By the end of the embryonic period, the embryo is approximately 3 cm (1.2 in) from crown to rump and weighs approximately 8 g (0.25 oz). |
What goes through different larval stages? | sponges | octopuses | plants | crustaceans | Figure 28.41 All crustaceans go through different larval stages. Shown are (a) the nauplius larval stage of a tadpole shrimp, (b) the cypris larval stage of a barnacle, and (c) the zoea larval stage of a green crab. (credit a: modification of work by USGS; credit b: modification of work by Mª. Mingorance Rodríguez; credit c: modification of work by B. Kimmel based on original work by Ernst Haeckel). |
What is the major cause of chronic respiratory disease as well as cardiovascular disease and cancer? | diet | drinking | exercise | smoking | Smoking is the major cause of chronic respiratory disease as well as cardiovascular disease and cancer. Exposure to tobacco smoke by smoking or by breathing air that contains tobacco smoke is the leading cause of preventable death in the United States. Regular smokers die about 10 years earlier than nonsmokers do. The Centers for Disease Control and Prevention (CDC) describes tobacco use as "the single most important preventable risk to human health in developed countries and an important cause of [early] death worldwide. " Simply stated: Stopping smoking can prevent many respiratory diseases. |
Monotremes, marsupials, and placental mammals are subclasses of what? | birds | amphibians | reptiles | mammals | Monotremes, marsupials, and placental mammals are subclasses of mammals. Almost all living mammals are placental mammals, which are divided into many orders. |
What type of mammal gives birth to young that need to develop further in the mother's pouch after birth? | aborigines | humans | whales | marsupials | Marsupials give birth to a tiny, immature embryo. The embryo then continues to grow and develop in a pouch on the mother’s belly. This is less risky for the mother. However, the embryo is fragile, so it may be less likely to survive than the fetus of a placental mammal. |
What is the measure of how closely molecules are packed together? | frequency | length | volume | density | Density is mass per unit volume. Density is a measure of how closely molecules are packed together. The closer together they are, the greater the density. Since air is a gas, the molecules can pack tightly or spread out. |
What is the leading cause of lung cancer? | tuberculosis | chewing tobacco | heredity | tobacco smoke | Tobacco smoke contains dozens of carcinogens, including nicotine and formaldehyde. Exposure to tobacco smoke is the leading cause of lung cancer. |
The golgi removes some sugar monomers and substitutes others, producing a large variety of what? | proteins | electrolytes | fats | carbohydrates | |
Parenchymal, collenchymal, and sclerenchymal cells are associated with what types of living things? | fungi | primates | parasites | plants | Different types of plant cells include parenchymal, collenchymal, and sclerenchymal cells. The three types differ in structure and function. |
What is the name of the location in which a stream or river starts? | mouth | spring | shore | source | All streams and rivers have several features in common. These features are shown in ( Figure below ). The place where a stream or river starts is its source. The source might be a spring, where water flows out of the ground. Or the source might be water from melting snow on a mountain top. A single stream may have multiple sources. A stream or river probably ends when it flows into a body of water, such as a lake or an ocean. A stream ends at its mouth. As the water flows into the body of water, it slows down and drops the sediment it was carrying. The sediment may build up to form a delta. |
What disease occurs when cells in the breast grow out of control and form a tumor? | muscular cyst | adult breast growth | muscle cancer | breast cancer | Breast cancer is the most common type of cancer in females. It occurs when cells in the breast grow out of control and form a tumor. Breast cancer is rare in teens but becomes more common as females get older. Regular screening is recommended for most women starting around age 40. If found early, breast cancer usually can be cured with surgery. |
What process refers to the changes that occur in populations of living organisms over time? | variation | spontaneous mutation | adaptation | evolution | The term evolution describes the changes that occur in populations of living organisms over time. Describing these changes does not address the origin of life. The two are commonly and mistakenly confused. Biological evolution likewise says nothing about cosmology, the Big Bang, or where the universe, galaxy, solar system, or Earth came from. |
Alkenes can react with what to form alcohols? | sugars | air | proteins | water | Alkenes can react with water to form alcohols. |
Wind blown sand contributes to what type of erosion? | filtration | vegetation | sedimentary | abrasion | Did you ever see workers sandblasting a building to clean it? Sand is blown onto the surface to scour away dirt and debris. Wind-blown sand has the same effect. It scours and polishes rocks and other surfaces. Wind-blown sand may carve rocks into interesting shapes. You can see an example in Figure below . This form of erosion is called abrasion. It occurs any time rough sediments are blown or dragged over surfaces. Can you think of other ways abrasion might occur?. |
Bases are ionic compounds consisting of hydroxide ions and a what? | sulfate | cinion | carbonate | cation | Bases are ionic compounds consisting of hydroxide ions and a cation. Naming and formula writing for bases follows the same guidelines as for other ionic compounds. |
What causes the menstrual cycle to be repeated? | ovaries | gravity | uteris | lack of fertilization | The menstrual cycle is a series of changes in the reproductive system of mature females that repeats every month on average. It includes changes in the uterus as well as development of an egg and ovulation. If fertilization does not occur, menstruation occurs and the cycle repeats. |
What happens when turgid cells in a nonwoody tissue push against each other? | the tissues merge | the tissue dies | the tissue melts | the tissue stiffens | |
What is the waxy substance that epidermal cells secrete? | saliva | cellulose | bile | cuticle | Dermal tissue covers the outside of a plant in a single layer of cells called the epidermis. You can think of the epidermis as the plant’s skin. It mediates most of the interactions between a plant and its environment. Epidermal cells secrete a waxy substance called cuticle , which coats, waterproofs, and protects the above-ground parts of plants. Cuticle helps prevent water loss, abrasions, infections, and damage from toxins. |
What is the length of the route between two points? | velocity | speed | direction | distance | Distance is the length of the route between two points. The distance of a race, for example, is the length of the track between the starting and finishing lines. In a 100-meter sprint, that distance is 100 meters. |
According to the first law of thermodynamics, what can neither be created nor destroyed? | light | fuel | food | energy | Chapter 46 1 Figure 46.8 According to the first law of thermodynamics, energy can neither be created nor destroyed. Eventually, all energy consumed by living systems is lost as heat or used for respiration, and the total energy output of the system must equal the energy that went into it. 3 Figure 46.17 C: Nitrification by bacteria converts nitrates (NO3−) to nitrites (NO2−). 4 D 6 B 8 A 10 D 12 D 14 B 16 A 18 A 20 C 21 Food webs show interacting groups of different species and their many interconnections with each other and the environment. Food chains are linear aspects of food webs that describe the succession of organisms consuming one another at defined trophic levels. Food webs are a more accurate representation of the structure and dynamics of an ecosystem. Food chains are easier to model and use for experimental studies. 23 Grazing food webs have a primary producer at their base, which is either a plant for terrestrial ecosystems or a phytoplankton for aquatic ecosystems. The producers pass their energy to the various trophic levels of consumers. At the base of detrital food webs are the decomposers, which pass this energy to a variety of other consumers. Detrital food webs are important for the health of many grazing food webs because they eliminate dead and decaying organic material, thus, clearing space for new organisms and removing potential causes of disease. By breaking down dead organic matter, decomposers also make mineral nutrients available to primary producers; this process is a vital link in nutrient cycling. 25 NPE measures the rate at which one trophic level can use and make biomass from what it attained in the previous level, taking into account respiration, defecation, and heat loss. Endotherms have high metabolism and generate a lot of body heat. Although this gives them advantages in their activity level in colder temperatures, these organisms are 10 times less efficient at harnessing the energy from the food they eat compared with cold-blooded animals, and thus have to eat more and more often. 27 Many factors can kill life in a lake or ocean, such as eutrophication by nutrient-rich surface runoff, oil spills, toxic waste spills, changes in climate, and the dumping of garbage into the ocean. Eutrophication is a result of nutrient-rich runoff from land using artificial fertilizers high in nitrogen and phosphorus. These nutrients cause the rapid and excessive growth of microorganisms, which deplete local dissolved oxygen and kill many fish and other aquatic organisms. |
What are the three primary pigment colors? | red, green, blue | red, white, blue | green, orange, purple | cyan, yellow, magenta | Pigments are substances that color materials by reflecting light of certain wavelengths and absorbing light of other wavelengths. The primary pigment colors are cyan, yellow, and magenta. They can be combined to produce all other colors. |
How do organophostbate pesticides work? | inhibiting testosterone | inhibiting reticulum | inhibiting cryptosporidium | inhibiting acetylcholinesterase | |
In the case of a light bulb, electricity is converted to light and what kind of energy? | chemical | nuclear | abstract | thermal | Most circuits have devices such as light bulbs that convert electric energy to other forms of energy. In the case of a light bulb, electricity is converted to light and thermal energy. |
Where in relation to the home, are levels of vocs found to be higher? | outdoors | On slopes | in Fields | indoors | The processes of evolution are fundamental to much of biology. Why do people have such a hard time understanding them?. |
Density and pressure of air decreases with what? | horizontal distance | temperature | humidity | altitude | Like density, the pressure of the air decreases with altitude. There is less air pressing down from above the higher up you go. Look at the bottle in Figure below . It was drained by a hiker at the top of a mountain. Then the hiker screwed the cap on the bottle and carried it down to sea level. At the lower altitude, air pressure crushed it. Can you explain why?. |
Energy is absorbed in the process of converting a liquid at its boiling point into a what? | solid | mesh | plasma | gas | Energy is absorbed in the process of converting a liquid at its boiling point into a gas. As with the melting of a solid, the temperature of a boiling liquid remains constant and the input of energy goes into changing the state. The molar heat of vaporization of a substance is the heat absorbed by one mole of that substance as it is converted from a liquid to a gas. As a gas condenses to a liquid, heat is released. The molar heat of condensation of a substance is the heat released by one mole of that substance as it is converted from a gas to a liquid. Since vaporization and condensation of a given substance are the exact opposite processes, the numerical value of the molar heat of vaporization is the same as the numerical value of the molar heat of condensation, but opposite in sign. In other words, . |
Images in what type of mirror are reversed left and right but not reversed top and bottom? | convex | concave | virtual | plane mirror | Images in a plane mirror are reversed left and right but not reversed top and bottom. |
What do cells produce as they age? | oxidants | carcinogens | wrinkles | proto-oncogenes | |
The body of the simplest sponges takes the shape of a cylinder with a large central cavity, called? | spirogyra | spicule | vacuole | spongocoel | The body of the simplest sponges takes the shape of a cylinder with a large central cavity, the spongocoel. Water enters the spongocoel from numerous pores in the body wall. Water flows out through a large opening called the osculum (Figure 15.9). However, sponges exhibit a diversity of body forms, which vary in the size and branching of the spongocoel, the number of osculi, and where the cells that filter food from the water are located. Sponges consist of an outer layer of flattened cells and an inner layer of cells called choanocytes separated by a jellylike substance called mesohyl. The mesohyl contains embedded amoeboid cells that secrete tiny needles called spicules or protein fibers that help give the sponge its structural strength. The cell body of the choanocyte is embedded in mesohyl but protruding into the spongocoel is a mesh-like collar surrounding a single flagellum. The beating of flagella from all choanocytes moves water through the sponge. Food particles are trapped in mucus produced by the sieve-like collar of the choanocytes and are ingested by phagocytosis. This process is called intracellular digestion. Amoebocytes take up nutrients repackaged in food vacuoles of the choanocytes and deliver them to other cells within the sponge. |
Laid on dry land by reptiles, amniotic eggs have what that prevents them from drying out? | oil coating | double shells | double yolks | waterproof membranes | Loggerhead turtles spend most of their life in the ocean. Adult female loggerheads go ashore briefly to lay their eggs in the sand. Then they return to the water and leave the eggs to hatch on their own. Figure below shows baby loggerheads on a beach shortly after hatching. The baby turtles must make their way back to the water, hopefully without being snatched up by a predator. Loggerhead turtles are reptiles. Unlike amphibians, turtles and other reptiles can lay their eggs on dry land. That’s because they produce amniotic eggs. Amniotic eggs have waterproof membranes to prevent them from drying out. |
What three rs represent the steps that you personally can take to conserve our natural resources and minimize waste? | reduce, reuse, re-educate | rinse, reuse, recycle | remove, reduce, reuse | reduce, reuse, recycle | Reduce, reuse, and recycle. There are steps that you personally can take to conserve our natural resources and reduce waste. The waste that an individual creates is small in proportion to all the waste produced by society. Yet all small contributions, when added up, make a difference. |
What is the process that allows organisms with better traits to survive and produce? | succession | spontaneous mutation | adaptation | natural selection | Evolution occurs by natural selection, the process by which organisms with traits that better enable them to adapt to their environment will tend to survive and reproduce in greater numbers. Evolution is due to differences in the survival and reproduction of individuals within a population. |
What is the term for a substance that increases the rate of a chemical reaction but is not changed or used up in the reaction? | a contribute | a mechanism | an acid | a catalyst | Some reactions need extra help to occur quickly. They need another substance, called a catalyst. A catalyst is a substance that increases the rate of a chemical reaction but is not changed or used up in the reaction. The catalyst can go on to catalyze many more reactions. |
What type of compounds can form crystals? | molecular compounds | integral compounds | magnetic compounds | ionic compounds | Many compounds form molecules, but ionic compounds form crystals instead. A crystal consists of many alternating positive and negative ions bonded together in a matrix. Look at the crystal of sodium chloride (NaCl) in the Figure below . The sodium and chloride ions are attracted to each other because they are oppositely charged, so they form ionic bonds. |
In grazing, a predator partially eats but does not kill what? | predators | time | pack | prey | In grazing , the predator eats part of the prey but does not usually kill it. You may have seen cows grazing on grass. The grass they eat grows back, so there is no real effect on the population. In the ocean, kelp (a type of seaweed) can regrow after being eaten by fish. |
Bone tissues include compact bone, spongy bone, bone marrow, and? | epithelium | cartilage | esophagus | periosteum | Bone tissues include compact bone, spongy bone, bone marrow, and periosteum. |
What type of bacteria causes the disease called tuberculosis? | streptococcus | E. coli | staphylococcus | mycobacterium | Tuberculosis (TB) is a common and often deadly disease caused by a genus of bacterium called Mycobacterium . Tuberculosis most commonly attacks the lungs but can also affect other parts of the body. TB is a chronic disease, but most people who become infected do not develop the full disease. Symptoms include a cough, which usually contains mucus and coughing up blood. |
Studies have shown that not only does reproduction have a cost as far as how long male fruit flies live, but also fruit flies that have already mated several times have limited amounts of this? | chromosomes | dna | eggs | sperm | Energy Budgets, Reproductive Costs, and Sexual Selection in Drosophila Research into how animals allocate their energy resources for growth, maintenance, and reproduction has used a variety of experimental animal models. Some of this work has been done using the common fruit fly, Drosophila melanogaster. Studies have shown that not only does reproduction have a cost as far as how long male fruit flies live, but also fruit flies that have already mated several times have limited sperm remaining for reproduction. Fruit flies maximize their last chances at reproduction by selecting optimal mates. In a 1981 study, male fruit flies were placed in enclosures with either virgin or inseminated females. The males that mated with virgin females had shorter life spans than those in contact with the same number of inseminated females with which they were unable to mate. This effect occurred regardless of how large (indicative of their age) the males were. Thus, males that did not mate lived longer, allowing them more opportunities to find mates in the future. More recent studies, performed in 2006, show how males select the female with which they will mate and [3] how this is affected by previous matings (Figure 45.8). Males were allowed to select between smaller and larger females. Findings showed that larger females had greater fecundity, producing twice as many offspring per mating as the smaller females did. Males that had previously mated, and thus had lower supplies of sperm, were termed “resource-depleted,” while males that had not mated were termed “nonresource-depleted. ” The study showed that although non-resource-depleted males preferentially mated with larger females, this selection of partners was more pronounced in the resource-depleted males. Thus, males with depleted sperm supplies, which were limited in the number of times that they could mate before they replenished their sperm supply, selected larger, more fecund females, thus maximizing their chances for offspring. This study was one of the first to show that the physiological state of the male affected its mating behavior in a way that clearly maximizes its use of limited reproductive resources. |
What are the two most common causes of diseases? | nutritional deficiencies | bacteria and protazoa | viruses and protazoa | bacteria and viruses | Today most people realize that microorganisms, such as bacteria or viruses, are the cause of disease. This concept is known as the germ theory of disease, one of the few scientific theories in the field of the life sciences. Although it seems obvious now, people did not always understand the cause of disease. How does a theory such as this become established?. |
Organic compounds are defined as covalently bonded compounds containing carbon, excluding carbonates and what else? | acids | gases | crystals | oxides | At one time in history, it was thought that only living things were capable of synthesizing the carbon-containing compounds present in cells. For that reason, the term organic was applied to those compounds. Eventually it was proved that carbon-containing compounds could be synthesized from inorganic substances, but the term organic has remained. Currently, organic compounds are defined as covalently bonded compounds containing carbon, excluding carbonates and oxides. By this definition, compounds such as carbon dioxide (CO 2 ) and sodium carbonate (Na 2 CO 3 ) are considered to be inorganic. Organic chemistry is the study of all organic compounds. |
What drives the turbine in a thermonuclear reactor? | wind energy | magnets | heated oil | heated water or steam | Scientists are searching for ways to create controlled nuclear fusion reactions on Earth. Their goal is develop nuclear fusion power plants, where the energy from fusion of hydrogen nuclei can be converted to electricity. You can see how this might work in the Figure below . In the thermonuclear reactor, radiation from fusion is used to heat water and produce steam. The steam can then be used to turn a turbine and generate electricity. |
What is the term for physicians and scientists who research and develop vaccines and treat and study conditions ranging from allergies to aids? | virologists | endocrinologists | vaccinologists | immunologists | Immunologist The variations in peripheral proteins and carbohydrates that affect a cell’s recognition sites are of prime interest in immunology. These changes are taken into consideration in vaccine development. Many infectious diseases, such as smallpox, polio, diphtheria, and tetanus, were conquered by the use of vaccines. Immunologists are the physicians and scientists who research and develop vaccines, as well as treat and study allergies or other immune problems. Some immunologists study and treat autoimmune problems (diseases in which a person’s immune system attacks his or her own cells or tissues, such as lupus) and immunodeficiencies, whether acquired (such as acquired immunodeficiency syndrome, or AIDS) or hereditary (such as severe combined immunodeficiency, or SCID). Immunologists are called in to help treat organ transplantation patients, who must have their immune systems suppressed so that their bodies will not reject a transplanted organ. Some immunologists work to understand natural immunity and the effects of a person’s environment on it. Others work on questions about how the immune system affects diseases such as cancer. In the past, the importance of having a healthy immune system in preventing cancer was not at all understood. To work as an immunologist, a PhD or MD is required. In addition, immunologists undertake at least 2–3 years of training in an accredited program and must pass an examination given by the American Board of Allergy and Immunology. Immunologists must possess knowledge of the functions of the human body as they relate to issues beyond immunization, and knowledge of pharmacology and medical technology, such as medications, therapies, test materials, and surgical procedures. |
Where are temperatures the lowest? | in asia | over the oceans | at the equator | at the poles | At the poles, the Sun’s rays are least direct. Much of the area is covered with ice and snow, which reflect a lot of sunlight. Temperatures are lowest here. |
Protecting the surface of metal prevents what? | evaporation | extraction | diffusion | corrosion | One way to prevent corrosion is to protect the surface of the metal. Covering the surface of the metal object with paint or oil will prevent corrosion by not allowing oxygen to contact it. Unfortunately, scratches in the paint or wearing off of the oil will allow the corrosion to begin. Corrosion-sensitive metals can also be coated with another metal that is resistant to corrosion. A “tin can” is actually made of iron coated with a thin layer of tin which protects the iron. |
What type of tissues are major barriers to the entry of pathogens into the body? | nasal | skin | vascular | mucosal | The Mucosal Immune Response Mucosal tissues are major barriers to the entry of pathogens into the body. The IgA (and sometimes IgM) antibodies in mucus and other secretions can bind to the pathogen, and in the cases of many viruses and bacteria, neutralize them. Neutralization is the process of coating a pathogen with antibodies, making it physically impossible for the pathogen to bind to receptors. Neutralization, which occurs in the blood, lymph, and other body fluids and secretions, protects the body constantly. Neutralizing antibodies are the basis for the disease protection offered by vaccines. Vaccinations for diseases that commonly enter the body via mucous membranes, such as influenza, are usually formulated to enhance IgA production. Immune responses in some mucosal tissues such as the Peyer’s patches (see Figure 21.11) in the small intestine take up particulate antigens by specialized cells known as microfold or M cells (Figure 21.27). These cells allow the body to sample potential pathogens from the intestinal lumen. Dendritic cells then take the antigen to the regional lymph nodes, where an immune response is mounted. |
Trash that gets into fresh and saltwater waterways is called what type of debris? | water | pollution | ocean | aquatic | Most protists consist of a single cell. Some are multicellular but they lack specialized cells. |
What is the term for genes that control the expression of other genes within specific regions of cells in the developing organism? | data genes | expression genes | age genes | gap genes | Gap genes control the expression of other genes within specific regions of cells in the developing organism. This allows specific genes to be expressed in certain cells at the appropriate stage of development. |
In vertebrates, what tissue is a type of connective tissue that supports the entire body structure? | collagen | cartilage | blood | bone | Complex Tissue Structure As multicellular organisms, animals differ from plants and fungi because their cells don’t have cell walls, their cells may be embedded in an extracellular matrix (such as bone, skin, or connective tissue), and their cells have unique structures for intercellular communication (such as gap junctions). In addition, animals possess unique tissues, absent in fungi and plants, which allow coordination (nerve tissue) of motility (muscle tissue). Animals are also characterized by specialized connective tissues that provide structural support for cells and organs. This connective tissue constitutes the extracellular surroundings of cells and is made up of organic and inorganic materials. In vertebrates, bone tissue is a type of connective tissue that supports the entire body structure. The complex bodies and activities of vertebrates demand such supportive tissues. Epithelial tissues cover, line, protect, and secrete. Epithelial tissues include the epidermis of the integument, the lining of the digestive tract and trachea, and make up the ducts of the liver and glands of advanced animals. The animal kingdom is divided into Parazoa (sponges) and Eumetazoa (all other animals). As very simple animals, the organisms in group Parazoa (“beside animal”) do not contain true specialized tissues; although they do possess specialized cells that perform different functions, those cells are not organized into tissues. These organisms are considered animals since they lack the ability to make their own food. Animals with true tissues are in the group Eumetazoa (“true animals”). When we think of animals, we usually think of Eumetazoans, since most animals fall into this category. The different types of tissues in true animals are responsible for carrying out specific functions for the organism. This differentiation and specialization of tissues is part of what allows for such incredible animal diversity. For example, the evolution of nerve tissues and muscle tissues has resulted in animals’ unique ability to rapidly sense and respond to changes. |
Red blood cells don't have a nucleus. this allows them to do what? | heal faster | be redder | move faster | carry more oxygen | Red blood cells ( Figure below ) are made in the red marrow of long bones, rib bones, the skull, and vertebrae. Each red blood cell lives for only 120 days (about four months). After this time, they are destroyed in the liver and spleen. Mature red blood cells do not have a nucleus or other organelles. Lacking these components allows the cells to have more hemoglobin and carry more oxygen. |
The number of electron pairs that hold two atoms together is called? | electron order | nuclear order | proton order | bond order | Summary Bond order is the number of electron pairs that hold two atoms together. Single bonds have a bond order of one, and multiple bonds with bond orders of two (a double bond) and three (a triple bond) are quite common. In closely related compounds with bonds between the same kinds of atoms, the bond with the highest bond order is both the shortest and the strongest. In bonds with the same bond order between different atoms, trends are observed that, with few exceptions, result in the strongest single bonds being formed between the smallest atoms. Tabulated values of average bond energies can be used to calculate the enthalpy change of many chemical reactions. If the bonds in the products are stronger than those in the reactants, the reaction is exothermic and vice versa. Saylor URL: http://www. saylor. org/books. |
What occurs when the immune system makes an inflammatory response to a harmless antigen? | immunity | antibodies | asthma attack | allergies | Allergies occur when the immune system makes an inflammatory response to a harmless antigen. An antigen that causes an allergy is called an allergen. |
What energy source, now making a comeback, has helped propel ships and pump water for many years? | solar energy | weather energy | geothermal energy | wind energy | The whirring blades of these wind turbines look stark against the darkening sky at sunset. The energy of the wind causes the blades to spin, and the energy of the spinning blades is used to generate electricity. People have been using wind for energy for centuries. Until about 200 years ago, for example, ships depended on wind to sail the oceans. And windmills have long been used to gather wind energy to pump water and do other useful work. Today, wind energy is making a comeback. Do you know why? What might be advantages of using the wind for energy? This chapter has the answers. |
What is it called when the nucleus of an atom splits into two smaller nuclei? | nuclear fusion | complex fission | cell division | nuclear fission | Nuclear fission is the splitting of the nucleus of an atom into two smaller nuclei. This releases a great deal of energy. Nuclear power plants use the energy from nuclear fission to generate electricity. |
The curie (ci) is one measure of the rate of what? | growth | spin | division | decay | The curie (Ci) is one measure of the rate of decay (named after Pierre and Marie Curie). One curie is equivalent to 3.7 × 10 10 disintegrations per second. Since this is obviously a large and unwieldy number, radiation is often expressed in millicuries or microcuries (still very large numbers). Another measure is the becquerel (Bq) , named after Henri Becquerel. The becquerel is defined as an activity of one disintegration/second. Both of these units are concerned with the disintegration rate of the radioactive isotope and give no indication of dosage to the target material. |
A unique type of organism is also known as what? | element | taxonomy | parasites | species | A species is a unique type of organism. Members of a species can interbreed and produce offspring that can breed (they are fertile). Organisms that are not in the same species cannot do this. Examples of species include humans, lions, and redwood trees. Can you name other examples?. |
Snakes use what anatomical structure to smell scents in the air? | forked eyes | forked tails | branched tongue | forked tongue | Most reptiles have good eyesight and a keen sense of smell. Snakes smell scents in the air using their forked tongue (see Figure below ). This helps them locate prey. Some snakes have heat-sensing organs on their head that help them find endothermic prey, such as small mammals and birds. Staring into the Beautiful Cold-Blooded Eyes of Reptiles at http://www. environmentalgraffiti. com/news-reptile-eyes is a pictorial display of numerous reptile eyes. |
What chemical element helps forms strong bones and teeth in humans? | magnesium | iron | potassium | calcium | Minerals are chemical elements that are essential for body processes. They include calcium, which helps form strong bones and teeth, and potassium, which is needed for normal nerve and muscle function. Good sources of minerals include leafy, green vegetables, whole grains, milk, and meats. |
The limit to how much solute will dissolve in a given amount of solvent is called what? | strength | density | potency | solubility | Solubility There is usually a limit to how much solute will dissolve in a given amount of solvent. This limit is called the solubility of the solute. Some solutes have a very small solubility, while other solutes are soluble in all proportions. Table 9.2 "Solubilities of Various Solutes in Water at 25°C (Except as Noted)" lists the solubilities of various solutes in water. Solubilities vary with temperature, so Table 9.2 "Solubilities of Various Solutes in Water at 25°C (Except as Noted)" includes the temperature at which the solubility was determined. Table 9.2 Solubilities of Various Solutes in Water at 25°C (Except as Noted). |
What occurs when hot magma transforms rock that it contacts? | changing metamorphism | existence metamorphism | form metamorphism | contact metamorphism | Contact metamorphism occurs when hot magma transforms rock that it contacts. |
What term refers to entities, events or powers regarded as being beyond nature, and cannot be explained by scientific means? | natural | hypothetical | fictional | supernatural | Science is based on the analysis of observations made either through our senses or by using special equipment. Science therefore cannot explain anything about the natural world that is beyond what is observable. The term supernatural refers to entities, events, or powers regarded as being beyond nature, in that such things cannot be explained by scientific means. They are not measurable or observable in the same way the natural world is, and are therefore considered to be outside the realm of scientific examination. |
What causes an elastic force in springs? | freezing | velocity | momentum | stretching or compressing | Springs like the ones in Figure below also have elastic force when they are stretched or compressed. And like stretchy materials, they return to their original shape when the stretching or compressing force is released. Because of these properties, springs are used in scales to measure weight. They also cushion the ride in a car and provide springy support beneath a mattress. Can you think of other uses of springs?. |
What effect is responsible for flight paths looking curved? | tonal effect | resonant effect | volumetric effect | coriolis effect | Zappy's. Flight paths look curved due to the Coriolis effect . CC BY-NC 3.0. |
Wetlands are environments in which the soil is either permanently or periodically saturated with what? | spores | hydrogen | oil | water | Wetlands Wetlands are environments in which the soil is either permanently or periodically saturated with water. Wetlands are different from lakes and ponds because wetlands exhibit a near continuous cover of emergent vegetation. Emergent vegetation consists of wetland plants that are rooted in the soil but have portions of leaves, stems, and flowers extending above the water’s surface. There are several types of wetlands including marshes, swamps, bogs, mudflats, and salt marshes (Figure 20.33). |
When the ground absorbs the water and it settles below the surface it is called what? | precipitation | wastewater | glacier | groundwater | |
Some metabolic pathways release what by breaking down complex molecules to simpler compounds? | water | fat | hydrogen | energy | |
What is the smallest portion of a crystal lattice? | element cell | ionic cell | function cell | unit cell | A unit cell is the smallest portion of a crystal lattice that shows the three-dimensional pattern of the entire crystal. A crystal can be thought of as the same unit cell repeated over and over in three dimensions. The Figure below illustrates the relationship of a unit cell to the entire crystal lattice. |
What is one major cause of skin cancer? | infrared light | visible light | sunscreen | ultraviolet light | The most important way to keep your skin healthy is to protect it from ultraviolet light. Over-exposure to ultraviolet light can cause skin cancer. Keeping the skin clean can help prevent acne. |
Which important decomposers are known to live just about anywhere on earth? | sporozoans | protazoas | viruses | archeans | Archaeans are now known to live just about everywhere on Earth. They are important decomposers. Many live in close relationships with other organisms. They are generally harmless and often beneficial. |
In the scientific method, what is the initial, unproven explanation for why something is occurring? | theories | concepts | idea | hypothesis | The scientific method is not a step by step, linear process. It is a way of learning about the world through the application of knowledge. Scientists must be able to have an idea of what the answer to an investigation should be. In order for scientists to make educated guesses about the answers, they will base their guesses on previous knowledge, with the notion of extending that knowledge. Scientists will often make an observation and then form a hypothesis to explain why a phenomenon occurred. They use all of their knowledge and a bit of imagination in their journey of discovery. |
What is the name of an element with a different number of neutrons? | solution | mineral | reaction | isotope | All atoms of the same element have the same number of protons, but some may have different numbers of neutrons. For example, all carbon atoms have six protons, and most have six neutrons as well. But some carbon atoms have seven or eight neutrons instead of the usual six. Atoms of the same element that differ in their numbers of neutrons are called isotopes . Many isotopes occur naturally. Usually one or two isotopes of an element are the most stable and common. Different isotopes of an element generally have the same physical and chemical properties. That’s because they have the same numbers of protons and electrons. For a video explanation of isotopes, go to this URL:. |
Nitrogen and sulfur oxides form what type of rain? | heavy rain | common rain | toxic rain | acid rain | Both nitrogen and sulfur oxides are toxic to humans. These compounds can cause lung diseases or make them worse. Nitrogen and sulfur oxides form acid rain, which is described in the next concept. |
Polyester fabric's resistance to wrinkling comes from the cross-linking of what? | wool strands | algae strands | velocity strands | polymer strands | PET is used in tires, photographic film, food packaging, and clothing. Polyester fabric is used in permanent-press clothing. Its resistance to wrinkling comes from the cross-linking of the polymer strands. |
What term refers to the sequence of community and ecosystem changes after a disturbance? | physiological succession | progressions | disturbance succession | ecological succession | |
What is the network of fibers that organizes structures and activities in the cell called? | DNA | enzymes | cytoplasm | cytoskeleton | 6.6 The cytoskeleton is a network of fibers that organizes structures and activities in the cell. |
Decreasing the volume of a gas and keeping everything else the same will cause its pressure to change in what way? | lower | heat up | decrease | increase | When gas molecules bump into things, it creates pressure. Pressure is greater when gas molecules occupy a smaller space, because greater crowding results in more collisions. This explains why decreasing the volume of a gas increases its pressure. |
What evolutionary strategy enables substantial activity during sleep for some animals? | mutation | hibernation | reproduction | adaptation | |
The cells of the blastocyst form an inner cell mass called the what? | xerophyte | blastocyst | chloroplast | embryoblast | The cells of the blastocyst form an inner cell mass and an outer cell layer, as shown in Figure below . The inner cell mass is called the embryoblast. These cells will soon develop into an embryo. The outer cell layer is called the trophoblast. These cells will develop into other structures needed to support and nourish the embryo. |
How do all musical instruments create sound? | conduction | condensation | stimulation | vibration | All musical instruments create sound by causing matter to vibrate. The vibrations start sound waves moving through the air. |
What system disorders include kidney stones, kidney failure, and urinary tract infections? | renal system | nervous system | digestive system | urinary system | Disorders of the urinary system include kidney stones, kidney failure, and urinary tract infections. |
What type of respiration has the advantage of releasing more energy? | elastic | kinetic | anaerobic | aerobic | A major advantage of aerobic respiration is the amount of energy it releases. Without oxygen, organisms can split glucose into just two molecules of pyruvate. This releases only enough energy to make two ATP molecules. With oxygen, organisms can break down glucose all the way to carbon dioxide. This releases enough energy to produce up to 38 ATP molecules. Thus, aerobic respiration releases much more energy than anaerobic respiration. |
Major climate types are based on what two things? | oxygen & precipitation | topography & temperature | environment & precipitation | temperature & precipitation | Major climate types are based on temperature and precipitation. These two factors determine what types of plants can grow in an area. Animals and other living things depend on plants. So each climate is associated with certain types of living things. A major type of climate and its living things make up a biome . As you read about the major climate types below, find them on the map in Figure above . |
When amino acids bind together, they form a long chain called what, which is an essential component of protein? | enzyme | peptide | lipids | polypeptide | When amino acids bind together, they form a long chain called a polypeptide . A protein consists of one or more polypeptide chains. A protein may have up to four levels of structure. The lowest level, a protein’s primary structure, is its sequence of amino acids. Higher levels of protein structure are described in Figure below . The complex structures of different proteins give them unique properties, which they need to carry out their various jobs in living organisms. You can learn more about protein structure by watching the animation at the following link: http://www. stolaf. edu/people/giannini/flashanimat/proteins/protein%20structure. swf . |
What type of cells does meiosis produce? | mutated cells | child cells | diploid daughter cells | haploid daughter cells | Meiosis is a special type of cell division. It produces haploid daughter cells. It occurs when an organism makes gametes. Meiosis is basically mitosis times two. The original diploid cell divides twice. The first time is called meiosis I. The second time is called meiosis II. However, the DNA replicates only once. It replicates before meiosis I but not before meiosis II. This results in four haploid daughter cells. |
Organisms that lack both a nucleus and membrane-bound organelles are known as what, in general? | trophic | photosynthetic | barren | prokaryotic | Two of the three domains—Bacteria and Archaea—are prokaryotic, meaning that they lack both a nucleus and true membrane-bound organelles. However, they are now considered, on the basis of membrane structure and rRNA, to be as different from each other as they are from the third domain, the Eukarya. Prokaryotes were the first inhabitants on Earth, perhaps appearing approximately 3.9 billion years ago. Today they are ubiquitous—inhabiting the harshest environments on the planet, from boiling hot springs to permanently frozen environments in Antarctica, as well as more benign environments such as compost heaps, soils, ocean waters, and the guts of animals (including humans). The Eukarya include the familiar kingdoms of animals, plants, and fungi. They also include a diverse group of kingdoms formerly grouped together as protists. |
What happens to most of the energy in a trophic level as it passes to the next higher level? | it stays the same | it increases | it is transferred | it is lost | |
What is the name for a specific amount of solute that can dissolve in a given amount of solvent? | concentration | humidity | viscosity | solubility | Solubility is a specific amount of solute that can dissolve in a given amount of solvent. |
What is freshwater below the earth's surface called? | precipitation | geyser | sediment | groundwater | Freshwater below Earth’s surface is called groundwater . The water infiltrates, or seeps down into, the ground from the surface. How does this happen? And where does the water go?. |
What forms when crystals precipitate out from a liquid? | plants sedimentary rocks | liquid sedimentary rocks | plasma sedimentary rocks | chemical sedimentary rocks | Chemical sedimentary rocks form when crystals precipitate out from a liquid. The mineral halite, also called rock salt, forms this way. You can make halite! Leave a shallow dish of salt water out in the Sun. As the water evaporates, salt crystals form in the dish. There are other chemical sedimentary rocks, like gypsum. |
What do people build to protect areas from floods? | sewers | reinforced walls | drains | dams | People protect areas that might flood with dams. In dire situations, they use sandbags ( Figure below ). Dams are usually very effective, but high water levels sometimes cause a dam to break. In that case, flooding can be catastrophic. Flood waters can also overflow a dam. People may line a river bank with levees to protect against floods. These are high walls that keep the stream within its banks during floods. Flood protection in one location sometimes causes problems elsewhere. For example, a levee in one location may just force the high water upstream or downstream. This will lead to flooding in a different location. Sometimes water gets so high that the river must be allowed to flood. |
What system of the body is responsible for ultimately ridding it of waste and excess water? | respiratory system | circulatory system | digestive system | excretory system | Toxic waste must be disposed of properly or there can be serious consequences. Now, your waste should not be as colorful or toxic as shown here (if it is, get yourself to a doctor as soon as possible), but it still needs to be removed from you. And that is the role of the excretory system. The excretory system gets rid of waste and excess water. |
What's it called when there's a sudden flow of mud? | dirt bath | avalanche | sediment | mudflow | A mudflow is the sudden flow of mud down a slope because of gravity. Mudflows occur where the soil is mostly clay. Like landslides, mudflows usually occur when the soil is wet. Wet clay forms very slippery mud that slides easily. Mudflows follow river channels, washing out bridges, trees, and homes that are in their path. |
Which zone is located below 200 meters from the surface? | mesopelagic | epipelagic | observable zone | aphotic zone | Below 200 meters is the aphotic zone. There are no primary producers here because there isn’t enough sunlight for photosynthesis. However, the water may be rich in nutrients because of dead organisms drifting down from above. Organisms that live here may include bacteria, sponges, sea anemones, worms, sea stars, and fish. |