Question: Primary cause of bleeding disorder in liver damage is due to


Question: Shifting of the oxygen dissociation curve to the right indicate

A rise in temperature or a fall in pH shifts the curve to the right.When the curve is shifted in this direction, a higher PO2 is required for hemoglobin to bind a given amount of O2.By decreasing o2 affinity more O2 is released to the tissue. Ref: Ganong's Review of Medical Physiology Twenty-Third Edition Page No:612

The affinity is less and more O2 is released to the tissue

Affinity is more and less oxygen is released to tissues


Question: Most potent stimulus for bile secretion

The bile salts have a number of impoant actions: they reduce surface tension and, in conjunction with phospholipids and monoglycerides, are responsible for the emulsification of fat preparatory to its digestion and absorption in the small intestine. They are amphipathic, that is, they have both hydrophilic and hydrophobic domains; one surface of the molecule is hydrophilic because the polar peptide bond and the carboxyl and hydroxyl groups are on that surface, whereas the other surface is hydrophobic. Therefore, the bile salts tend to form cylindrical disks called micelles. Their hydrophilic poions face out and their hydrophobic poions face in. Above a ceain concentration, called the critical micelle concentration, all bile salts added to a solution form micelles. Lipids collect in the micelles, with cholesterol in the hydrophobic center and amphipathic phospholipids and monoglycerides lined up with their hydrophilic heads on the outside and their hydrophobic tails in the center. The micelles play an impoant role in keeping lipids in solution and transpoing them to the brush border of the intestinal epithelial cells, where they are absorbed. Ninety to 95% of the bile salts are absorbed from the small intestine. Once they are deconjugated, they can be absorbed by nonionic diffusion, but most are absorbed in their conjugated forms from the terminal ileum (Figure 26-18) by an extremely efficient Na+-bile salt cotranspo system powered by basolateral Na+-K+ATPase. The remaining 5-10% of the bile salts enter the colon and are conveed to the salts of deoxycholic acid and lithocholic acid. Lithocholate is relatively insoluble and is mostly excreted in the stools; only 1% is absorbed. However, deoxycholate is absorbed. The absorbed bile salts are transpoed back to the liver in the poal vein and excreted in the bile (enterohepatic circulation). Those lost in the stool are replaced by synthesis in the liver; the normal rate of bile salt synthesis is 0.2 to 0.4 g/d. The total bile salt pool of approximately 3.5 g recycles repeatedly the enterohepatic circulation; it has been calculated that the entire pool recycles twice per meal and six to eight times per day. When bile is excluded from the intestine, up to 50% of ingested fat appears in the feces. A severe malabsorption of fat-soluble vitamins also results. When bile salt reabsorption is prevented by resection of the terminal ileum or by disease in this poion of the small intestine, the amount of fat in the stools is also increased because when the enterohepatic circulation is interrupted, the liver cannot increase the rate of bile salt production to a sufficient degree to compensate for the loss.REF: GANONG&;S REVIEW OF MEDICAL PHYSIOLOGY, KIM BARRETT, HEDDWEN BROOKS, SCOTT BOITANO, SUSAN BARMANTWENTY THIRD EDITIONPAGE NO:438,439,440


Question: Intrinsic factor in stomach is secreted by

In the body of the stomach, including the fundus, the glands also contain parietal (oxyntic) cells,which secrete hydrochloric acid and intrinsic factor, and chief (zymogen, peptic) cells, which secrete pepsinogens Ref: guyton and hall textbook of medical physiology 12 edition page number:406,407,408


Question: Sertoli cell feedback mechanism involves

Ans (b) Decreased FSH(Ref: Ganong, 25th ed/p.417)Sertoli cells produce the hormone inhibin which inhibits pituitary FSH (negative feedback)LH acts on the Leydig cells of testis to increase the production and secretion of testosterone which inhibits LH (negative feedback).


Question: Impulse is generated at fastest rate in

Some cardiac fibers have the capability of self-excitation, a process that can cause automatic rhythmical discharge and contraction. This capability is especially true of the fibers of the hea's specialized conducting system, including the fibers of the sinus node. For this reason, the sinus node ordinarily controls the rate of beat of the entire heaRef: Guyton and Hall textbook of medical physiology 13th edition. Page:123


Question: Continuous administration of GnRH

Gonadotropin-releasing hormone (GnRH) a decapeptide hormone from the hypothalamus that stimulates the anterior pituitary to release both follicle-stimulating hormone and luteinizing hormone.Endocrine hormone synthesis and secretion is controlled and regulated by a closed loop system. Negative feedback loops maintain optimal levels of each hormone in the body. If there are abnormally high levels of a hormone in the blood, feedback to the gland responsible for its production inhibits secretion. If there are abnormally low levels, the gland is stimulated to step up production and secretion. In this way, a homeostatic balance is maintained.Ref: Ganong&;s review of medical physiology;24th edition

Stimulates hypothalamic - pituitary axis

Suppresses hypothalamic - pituitary axis

May suppress or stimulate hypothalomic -pituitary axis

Has no effect on hypothalamic - pituitary axis


Question: Characteristics of blood flow in capillaries


Question: Emotional effect to a physical stimulus is given by

Emotion to sensory experiences (e.g. physical stimulus) is given by limbic system (especially amygdala).
"Limbic system adds feeling to sensory experiences and then lets these feelings direct behavior".
Hippocampus is involved in emotional memory.


Question: During spermatogenesis Sertoli cells secrete

Ans. C InhibinRef: Ganong Physiology, 24th ed. pg, 419 and 420; Guyton's Physiology, 11th ed. pg. 1007* The walls of the seminiferous tubules are lined by primitive germ cells and Sertoli cells.* Maturation of spermatozoa takes place in deep folds of the cytoplasm of the sertoli cells.* Mature spermatozoa are released from the Sertoli cells and become free in the lumens of the tubules. The sertoli cells secrete androgen binding protein (ABP), inhibin, and MIS.* Inhibin inhibits follicle-stimulating hormone (FSH) secretion.* Inhibin has a strong direct effect on the anterior pituitary gland to inhibit the secretion of FSH and possibly a slight effect on the hypothalamus to inhibit secretion of GnRH.Extra Mile* Testosterone, secreted by the Leydig cells* Luteinizing hormone--by anterior pituitary gland, stimulates the Leydig cells to secrete testosterone.* FSH--also by the anterior pituitary gland, stimulates the Sertoli cells; essential for spermatogenesis.


Question: Stimulation for gastric emptyinga) Secretinb) CCKc) Gastrind) Distension

Distension of stomach by food leads to peristaltic wave to empty the gastric content. Gastrin also increases gastric emptying.


Question: Blood testis barrier are present in

A. i.e. (Sertoli cells) (424- Ganong 22nd) (403 - Ganong 23rd)* Tight junctions between adjacent sertoli cells near the basal lamina form a blood -testis barrier* It prevents the entry of many substances from testicular interstitium into the lumen of seminiferous tubules* Functions of sertoli cells1. Support and nourish the germ cells till the spermatozoa are released from them2. Provide hormonal and other substances necessary from spermatogenesis3. Convert androgens into estrogen4. Secrete - androgen binding protein (ABP)**, Inhibin** Mullerian regression factor (MRF), Mullerian inhbiting substance (MIS)Blood testis barrier helps maintaining the composition of the fluid in the lumen of the seminiferous tubules and also protects the germ cells from blood borne noxious agentsIt also prevents antigenic products of germ cell division from entering the circulation and generating an autoimmune responseIt contains high concentration of androgens, oestrogens, K+, inositol glutamic and aspartic acid with low content of protein and glucose (808 - A.K. Jain 3rd)


Question: Normal vital capacity in an adult is

Vital capacity Amount of air that can be exhaled with maximum effo after maximum inspiration (ERV + TV + IRV); used to assess strength of thoracic muscles as well as pulmonary function. Around 4700mlRef: Ganong review of medical physiology 23rd edition Page no: 593


Question: Buffering action of haemoglobin is mainly due to

The buffering action of hemoglobin is due to the imidazole group of the hystadine residues. Hemoglobin molecule contains 38 histidine. imidazole group of deoxyhemoglobin dissociate less than those of oxyhaemoglobin. Ref: Page no 566 Textbook of physiology Volume 1 AK Jain 7th edition


Question: Fine touch is lost in lesion of

Dorsal column pathway is the principal direct pathway to the cerebral coex for fine touch, vibration sense, & proprioception.Ref: Ganong&;s Review of medical physiology;23 rd edition; pg: 173


Question: Glucose is transpoed in the presence Na+ ions in intestine. This is a type of

The active transpo of Na+ into the ECF by Na+-K+ pump is coupled to the transpo of other substances across the cell membrane against their concentration gradient. The energy for the transpo is not directly derived from ATP hydrolysis. Na+ Cotranspo of glucose is an example(Ref: Diseases. Textbook of medical physiology-Geetha)


Question: Most permeable to pure phospholipid bilayer

Phospholipid bilayer act as amphipathic molecule. Oxygen is most permeable. (REF. GANONG&;S REVIEW OF MEDICAL PHYSIOLOGY 24 EDITION, PAGE NO - 36)


Question: The action potential of the sinoatrial node

The action potential of the sinoatrial node and atrioventricular node results from the opening of the slow Ca2+ channels and the influx of Ca2+ (some Na+ may also enter through these slow Ca2+ channels). An action potential is elicited when the membrane potential reaches threshold. Spontaneous depolarization is an intrinsic propey of nodal tissue and can occur in the absence of nerves. The low resting potential results in a small action potential that propagates slowly. The rapid Na+ channels are inactivated in nodal tissue. An increase in the conductance to K+ would hyperpolarize the membrane.

Reuslts from the activation of rapid Na+ channels

Results from opening of the slow Ca2+ channels

Is equivalent in height and conduction velocity to that of the atrial muscle

Results from an increase in conductance to K+


Question: Most impoant buffer system present in the distal convoluted tubule

Ammonia acts as buffer in DCT and PCT. Ref: Ganong's review of medical physiology; 24th edition; page no: 713


Question: Gamma motor neurons are mainly influenced by

Gamma motor neurones are mainly influenced by rubrospinal tract Ref: guyton and hall textbook of medical physiology 12 edition page number:765,766,767


Question: Impaired function of Aquaporin results in

ADH acts V2 receptors on DCT casuing facultative reabsorption of water by inseing Aquaporin -2 channels into apical (luminal side ). Nephrogenic DI-defect in aquaporins BATER SYNDROME - Autosomal recessive Defect in"Na-K-2Cl cotranspoer, Cl channel & ROMK"in loop of Henle LIDDLE SYNDROME - Gain of function of epithelial Na channel (ENaC) Cystic fibrosis - CH-7 defect in CFTR gene - causing defect in transmembrane chloride ion regulation.


Question: In intersegmental reflex, the afferents come from

Ans. (d) Muscle spindles(Ref: Ganong, 25th ed/p.230)Stretch reflex is an intersegmental reflexWhen a skeletal muscle with an intact nerve supply is stretched with in physiological limits, it contracts. This response is called the stretch reflexThe receptor for this stretch reflex is muscle spindles


Question: Selenium is an essential component of


Question: Hb O2 dissociation curve to left by

Oxygen saturation curve Physiology A curve that describes the relationship between Hb O2 saturation and tension; defined by a sigmoid curve which reflects the interaction of the 4 Hb molecules involved in O2 uptake, transpo and release; a &;right shift&; of the curve indicates | Hb affinity for O2, as occurs in | pH-ie,acidosis, | temperature, | PCO2, while a &;left shift&; indicates | O2 affinity with | pH, | temperature, | 2,3 DPG and | PCO2Right shifts Acidosis, hypehermia, alveolar hypoventilation, anemia Left shifts Alkalosis, hypothermia, hyperventilation, carboxyhemoglobinemia, hypophosphatemia, | fetal Hb.Ref: Ganong&;s Review of Medical Physiology; 24th edition; page no:642


Question: Aquaporin channel mediated through ADH

Vasopressin * Vasopressin - secreted by suprachiasmatic nuclei of hypothalamus and transpoed to posterior pituitary * Biologic half life - 18 min * Vasopressin receptors:- V1A and V1B V1A and V1 B:- * G protein coupled receptor that acts phosphatidylinositol hydrolysis to increase intracellular Ca++ concentration * V1A - mediate vasoconstrictor effect * V1B - also called V3 receptors- specific to anterior pituitary - mediate secretion of ACTH V2 receptor:- * G protein coupled receptor that acts through Gs to increase cAMP * Antidiuretic action * Mechanism of action - inseion of aquaporin 2 into the apical membranes of the principal cells of collecting duct. Factors affecting vasopressin secretion Ref:- Ganong's Review of Medical Physiology 25th ed; pg num:- 696


Question: The fluidity of the plasma membrane is increased by

Cholesterol maintains the fluidity of the membrane. Cholesterol acts as a buffer to modify the fluidity of membranes. A lipid bilayer made up of only one type of phospholipid changes from a liquid state to a rigid crystalline state (gel state) at a characteristic freezing point. This change in state is known as a phase transition, and the temperature at which it occurs is called the phase transition temperature (Tm). The Tm is higher (fluidity is low) when the constituent fatty acid chains are long and mostly saturated (without double bonds). Long chains have greater interactions among themselves, making the membrane stiffer. Saturated fatty acids have straight tails, whereas unsaturated fatty acids have kinked tails. As more kinks are inseed in the tails, the membrane becomes less tightly packed, and therefore its fluidity increases. .


Question: Amplitude of action potential is predominantly determined by

Impermeant Negatively Charged Ions (Anions) Inside the Nerve Axon. Inside the axon are many negatively charged ions that cannot go through the membrane chan- nels. They include the anions of protein molecules and of many organic phosphate compounds, sulfate compounds, and so foh. Because these ions cannot leave the interior of the axon, any deficit of positive ions inside the membrane leaves an excess of these impermeant negative anions. Therefore, these impermeant negative ions are responsible for the negative charge inside the fiber when there is a net deficit of positively charged potassium ions and other posi- tive ions. Chlorine is the most common impermeant negative charge in the axon membrane Ref guyton and hall textbook of medical physiology 12/e p64


Question: Hardest tissue in humans

Ans: a (Enamel)Hardest tissue in humans is enamel.


Question: Prostaglandin was discovered from

Prostaglandins were believed to be pa of the prostatic secretions, and eventually were discovered to be produced by the seminal vesicles. ... The biochemists Sune K. Bergstrom, Bengt I. Samuelsson and John R. Vane jointly received the 1982 Nobel Prize in Physiology or Medicine for their research on prostaglandins. Ref: guyton and hall textbook of medical physiology 12 edition


Question: Calorific value of protein is

Combustometer is a wrong terminology given to confuse the aspirants.
A bomb calorimeter device is used to measure energy released by combustion of foodstuffs outside the body. It uses Direct Calorimetry to measure the calorific value.
Calorific value of various substances as measured in a bomb calorimeter are
Carbohydrate 4.1 kcal/g
Fat 9.3 kcal/g
Protein is 5.3 kcal/g
Note: if measured inside the body carbohydrate and Fat have same as above values but protein has 4.1 kcal/g

9.3 kcal/g as measured by bomb calorimeter.

5.3 kcal/g as measured by bomb calorimeter


Question: Plasma volume is best evaluated by using

Plasma volume is measured using dyes like Evans blur that binds specifically to plasma proteins.(Ref: Textbook of physiology N Geetha 2nd edition page no.62)


Question: Passive transfer of solvent occurs in

Osmosis is the passive flow of the solvent into a region where there is a higher concentration of a solute to which the membrane is impermeable.(Ref: Textbook of physiology AK Jain 5th edition page no.14)


Question: Largest % of blood volume in

At rest,At least 50% of the circulating blood volume is in the systemic veins, 12% is in the hea cavities, and18% is in the low-pressure pulmonary circulation.Only 2% is in the aoa, 8% in the aeries,1% in the aerioles, and5% in the capillariesRef: Ganong's Review of Medical Physiology Twenty-Third Edition Page No:543


Question: Pain sensitive intracranial structure is

Pain-Sensitive Structures. Headache is caused by traction, displacement, inflammation, vascular spasm, or distention of the pain-sensitive structures in the head or neck. Isolated involvement of the bony skull, most of the dura, or most regions of brain parenchyma does not produce pain. Ref: guyton and hall textbook of medical physiology 12 edition page number: 687,688,689


Question: Korotkoff sound is produced due to

When the cuff pressure is great enough to close the aery during pa of the aerial pressure cycle, a sound is then heard with each pulsation. These sounds are called Korotkoff sounds, named after Nikolai Korotkoff, a Russian physicianRef: Guyton and Hall textbook of medical physiology 13th edition. Page:182


Question: Inability to perform rapid alternating repeated movements is

Inability to perform rapid alternating repeated movements is dysdiadochokinesia Ref: Ganong 25th ed/page 251


Question: Mean arterial pressure is calculated as

Ans. (a) (SBP+2DBP)/3Ref: Ganong, 25th ed/p.577Mean arterial blood pressure (MAP)Is the average pressure in the arteriesSince the diastole of cardiac cycle is longer (0.53s) than the systole (0.27 s), mean is not the exact average of SBP and DBPMean arterial blood pressure = Diastolic pressure +1/3 of pulse pressureSince pulse pressure =SBP-DBP,MAP=DBP+1/3(SBP-DBP)MAP=3SBP+2DBP Normal mean arterial pressure is around 93-100mmHg


Question: The Efferent fibers bundle of the substantia nigra transmits dopamine to one of the following areas

Ans. (b) Corpus striatum(Ref: Ganong, 25th ed/p.243)The Efferent fibers bundle of the substantia nigra transmits dopamine to corpus striatum


Question: Peripheral cell membrane proteins are

There is dense accumulation of adhesion molecules on both the surfaces of the membrane with fibres extending from the cytoplasmic surface of each membrane into the cell.(Ref.Textbook of physiology AK Jain 5th edition page no.9)


Question: Agranular endoplasmic reticulum is involved in the synthesis of

Agranular Endoplasmic reticulum is also called smooth Endoplasmic reticulum. It is the site of steroid synthesis and detoxification. Granular is involved in protein synthesis.(REF: Ganong&;s Review of medical physiology)


Question: Intention tremor is a feature of


Question: Frontal lobe function

The frontal lobe plays a large role in voluntary movement. It houses the primary motor coex. The function of the frontal lobe involves the ability to project future consequences resulting from current actions, the choice between good and bad actions (or better and best) (also known as conscience), the override and suppression of socially unacceptable responses, and the determination of similarities and differences between things or events. Ref: guyton and hall textbook of medical physiology 12 edition page number:841,842,843


Question: Juxta glamerular cells secretes

i.e. (Renin): (670-Ganong 23rd)RENIN - is a glycoprotein hormone secreted by the granular cells (Juxtaglomerular cells) of the Juxta glomerular apparatus.* Juxtaglomerular apparatus (JGA) lies at hilum of glomerulus** (Juxta means near)Secretion of renin is stimulated by four factors1. Fall in arterial blood pressure2. Reduction in the volume of extracellular fluid3. Increased sympathetic activity4. Decreased load of sodium and chloride in macula densaATRIAL - NATRIURETIC PEPTIDE : secreted by atrial musculature of the heart*** ANP increases excretion of sodium ions through urine (natriuresis)* ANP causes dilatation of vessels (vasodilation) and lowering blood pressure* ANP is responsible for escape phenomenon and prevention of edema in primary hyperaldosteronism in spite of increased volume of ECFERYTHROPOIETIN is secreted by interstitial cells in the peritubular capillary bed of kidney (85%) and by perivenous hepatocytes in the liver (15%)The principal site of inactivation of erythropoietin is the liverANGIOTENSINOGEN - synthesized in the liver*Its circulating level is increased by glucocorticoids thyroid hormones, estrogen, several cytokines and angiotensin II


Question: Minimum urine osmolality that can be human kidney

Minimum urine osmolality that can be human kidney is 50mOsm/L Ref: Guyton textbook of medical physiology; 12th edition; page no: 345


Question: Resting membrane potential depends mainly on

Since K+ permeability is greater than Na+ permeability, therefore, K+ channels maintain the RMP.(Ref: Textbook of physiology AK Jaun 5th edition Page no.35)


Question: Osmoreceptor is located in

Ans. (c) Anterior hypothalamus(Ref: Ganong, 25th ed/p.308)Osmoreceptors maintain water balance and osmolarityThey are located in anterior hypothalamus


Question: The normal value of P50 on the oxyhaemoglobin dissociation curve in an adult is

Adult Hb- 50% saturation at PO2 of 26mmHg.
1mmHg= 0.133 KPa
26mmHg= 0.133 X 26 = 3.45


Question: Increase in P50 in oxygenation curve is due to decrease in

The strength with which oxygen binds to hemoglobin is affected by several factors. These factors shift or reshape the oxyhemoglobin dissociation curve. A rightward shift indicates that the hemoglobin under study has a decreased affinity for oxygen. ... Left shift: higher O2 affinity Ref: guyton and hall textbook of medical physiology 12 edition page number: 354,355,356


Question: Aromatase produces estrogen from

Oestrogen is produced from androgen by an enzyme aromatase Ref: guyton and hall textbook of medical physiology 12 edition page number:630,631,632


Question: ACTH secretion is inhibited by

Glucocoicoids inhibit ACTH secretion by a direct negative feedback mechanism. They also inhibit CRH secretion. Ref: Guyton and Hall 13th edition Pgno: 977


Question: Plateau phase of cardiac muscle is due to

Ca2+ influx through more slowly opening Ca2+ channels produces the plateau phase The initial depolarization is due to Na+ influx through rapidly opening Na+ channels Repolarization is due to net K+ efflux through multiple types of K+ channels Ref: Ganong's Review of Medical Physiology Twenty-Third Edition Page No:491


Question: Actin's active site is covered by

The active site of actin in skeletal muscles is where myosin binds. This is covered by Tropomyosin.


Question: Motilin is secreted by cells in

Motilin is a hormone released from endocrine cells within the epithelium of small intestine. Ref: Guyton,11e


Question: Preservation used for storing blood for transfusion is

citrate phosphate dextrose (CPD) a solution containing citric acid, sodium citrate, monobasic sodium phosphate, and dextrose that is the primary anticoagulant used for preservation of whole blood or red blood cells for up to 21 days Ref: guyton and hall textbook of medical physiology 12 edition page number:146,147,148


Question: Serum does not contain

Serum has essentially the same composition as plasma, except that its fibrinogen and clotting factors II, V, and VIII (Table 32-5). (Ref: Ganong's review of medical physiology 23rd Edition page no.530)


Question: Critical Closing volume is

Ans is 'd' i.e. Close to Residual Volume [Ref: Physiologic Basis of Respiratory> Disease by Qutayba Hamid, Joanne Shannon, James Martin pi37; Surgical Critical Care and Emergency Surgery: Clinical Questions and Answers By Forrest O. Moorep7; http://www.ccmtutorials.com/rs/peep/page4.htmCritical closing volume is the minimum volume and pressure of gas necessary to prevent small airway collapse. It is somewhat near Residual volume.Under pathological conditions when CCV exceeds Functional Residual Capacity (FRC), alveolar collapse occurs.FRC is = Residual volume + Expiratory reserve volume

Volume at the end of forceful expiration

Volume at the end of forceful inspiration

Volume remaining after Functional Residual Capacity is measured


Question: Parasympathetic stimulation causes

(C) Pupillary constriction # Parasympathetic effects on the organ systems:> GIT: Molility and tone are increased; Secretions are increased; Sphincters are relaxed (usually)> Lungs: Bronchial muscles undergo contraction; Bronchial glands are stimulated> Eyes: Radial muscle of Iris has no action; Sphincter muscle of Iris -- contraction; Ciliary muscle: contraction for near vision> Sweat glands: No response to parasympathetic stimulation. While sweat glands respond to cholinergic stimulation by genized increase in secretion they do not parasympathetic stimulation by the same.


Question: Gastric acid decreased by

When hydrochloric acid passes from the stomach into the duodenum, secretin is released into the bloodstream and stimulates the acinar cells of the pancreas to secrete water and bicarbonate into the pancreatic ducts that drain into the duodenum. By this mechanism, hydrochloric acid secreted by the stomach, which can be damaging to the intestinal lining, is promptly diluted and neutralized. Secretin also inhibits the secretion of gastrin, which triggers the initial release of hydrochloric acid into the stomach, and delays gastric emptyingref: guyton and hall textbook of medical physiology 12 edition page number: 409,410,411


Question: Carotid Sinus baroreceptor is most sensitive to

carotid sinus baroreceptor is most sensitive to mean aerial pressure(MAP) Maximal baroreceptor sensitivity is seen near the normal MAP. Very Small changes in aerial pressure around this is normal MAP dramatically alters baroreceptor firing to ensure normal aerial pressure is maintained. Baroreceptors Stretch receptors located in the hea and adventitia of the blood vessels. Types based on location Carotid Sinus and aoic arch receptors(high pressure regions) Cardiopulomonary receptors (low-pressure regions) 3. Afferents Carotid sinus - a branch of glossopharygeal nerve (IX CN)- the carotid sinus nerve (sinus nerve of hering) Aoic arch receptor- a branch of vagus nerve ((X CN) - aoic depressor nerve 4. Center for Reflex Medulla (Nucleus of tractus solitarius) 5. Efferents Sympathetic and parasympathetic neuronsto hea and vasculature Most sensitive to MAP The threshold for excitation: 50mmHg Maximal activity: 200mg 6. Responses when one carotid sinus is isolated and perfused and the other baroreceptors are denervated Perfusion pressure <30 mmHg: no response 70-110 mmHg: the linear relationship between perfusion pressure and the fall in systemiic BP and HR.. >150 mmHg: No fuher increase in response to the degree of inhibition of sympathetic nerve is maximal. Ref: Mosby&;s Cardiovascular Physiology Pgno: 185


Question: Maximum radiation exposure is by

Examination Effective total dose (mSv) Chest radiograph 0.06 Skull radiograph 0.2 Pelvis radiograph 0.65 Lumbar spine radiograph 1.3 Upper GI series (Barium) 2.45 Abdomen radiograph 0.55 Barium enema 2.8 to 4 IVP/IVU 1.6 Extremities 0.01 Enteroclysis 1.5 CT chest 8 CT abdomen 10 CT head 3.5 RNI 4.8


Question: White fibers are present in

Ans. (b) Extraocular muscles(Ref: Ganong, 25th ed/p. 108)Motor unit innervates very few (three to six) muscle fibers in muscles concerned with fine, precise, graded movements like extra ocular muscles and hand muscles - these are the white muscle fibers


Question: After laryngectomy, dynamic oesophageal voice is produced from

Esophageal speech is a skill that can help patients to communicate after a laryngectomy, the most common surgery used for the treatment of laryngeal cancer. ... This hole is called a tracheostoma; the patient uses it to breathe through and cough through after the operation. Ref otolaryngology dhingra 3e


Question: Speed of conduction is fastest in


Question: Vomiting centre

Vomiting refers to the forceful expulsion of contents from stomach and intestine. Vomiting centre is situated in the reticular formation of medulla oblongata near the vagal nucleus. Vomiting may be initiated by either activation of vomiting centre or by an activation of the chemoreceptor trigger zone. It may be activated directly or through afferents: Direct activation of the vomiting centre Afferent impulses activating vomiting centre. Sequence of mechanical events of vomiting: Pre-ejection phase Retching phase Ejection phase. Ref: guyton and hall textbook of medical physiology 12 edition page number:442,443,444


Question: In obesity, leptin level

Leptin is an adipocyte-derived, satiety-regulating hormone that acts within the hypothalamus and other brain sites. Obese humans and animals are largely resistant to central actions of leptin. Rising leptin levels associated with progressing obesity are generally regarded as simply a consequence rather than a causative factor in the leptin resistance and obesity. Ref: guyton and hall textbook of medical physiology 12 edition page number:811,812,813


Question: The velocity of conduction in the Purkinje fibers of the heart is


Question: Palpation on the costoveebral angle produces pain and tenderness in acute adrenal insufficiency. This is

Costoveebral angle pain and tenderness in acute adrenal insufficiency is known as Rogoff's sign


Question: Glucagon acts on muscle to cause

Glucagon - a polypeptide hormone secreted by the alpha cells of the islets of Langerhans in response to hypoglycemia or to stimulation by growth hormone. It increases blood glucose concentration by stimulating glycogenolysis in the liver and can be administered parenterally to relieve severe hypoglycemia from any cause, especially hyperinsulinism.Ref: Ganong&;s review of medical physiology; 24th edition page no: 432


Question: &;Bends&; are due to

Clinicians recognize three categories of DCS (Decompression Sickness).Mild or type I DCS can include sho-lived mild pains ("niggles"), pruritus, a skin rash, and deep throbbing pain ("bends") resulting from bubbles that form in muscles and joints. Serious or type II DCS can include symptoms in the CNS, lungs, and circulatory system. The CNS disorder--most commonly involving the spinal cord--reflects bubble formation in the myelin sheath of axons that compromises nerve conduction. Symptoms may range from dizziness ("staggers") to paralysis. Pulmonary symptoms ("chokes")--resulting from gas emboli in the pulmonary circulation--include burning pain on inspiration, cough, and respiratory distress. In the circulatory system, bubbles can not only obstruct blood flow but also trigger the coagulation cascade and lead to the release of vasoactive substances. Hypovolemic shock is also a pa of this syndrome. The third category is aerial gas embolization, in which large gas emboli can have catastrophic consequences unless the victim receives immediate recompression treatment.

Escape of nitrogen bubbles from the myelin sheath of motor nerves

Blockage of pulmonary capillaries by the nitrogen bubbles

Blockage of blood vessels of brain and spinal cord

Nitrogen bubbles that form in muscles and joints


Question: LH is secreted by

Luteinizing hormone (LH, also known as lutropin and sometimes lutrophin is a hormone produced by gonadotropic cells in the anterior pituitary gland. In females, an acute rise of LH ("LH surge") triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell-stimulating hormone (ICSH), it stimulates Leydig cell production of testosterone. It acts synergistically with FSH.Ref: Ganong&;s review of medical physiology; 24th edition; page no:-304


Question: Not controlled directly by ACTH

ACTH acts on the adrenal coex forming glucocoicoids and mineralocoicoidsRef: Ganong&;s review of medical physiology; 24th edition page no - 362


Question: Saltatory conduction in myelinated axons results from the fact that

"Saltatory" Conduction in Myelinated Fibers from Node to Node: Even though almost no ions can flow through the thick myelin sheaths of myelinated nerves, they can flow with ease through the nodes of Ranvier.Therefore, action potentials occur only at the nodes. Yet the action potentials are conducted from node to node, this is called saltatory conduction.That is, electrical current flows through the surrounding extracellular fluid outside the myelin sheath, as well as through the axoplasm inside the axon from node to node, exciting successive nodes one after another. Thus, the nerve impulse jumps along the fiber, which is the origin of the term "saltatory."Ref: Guyton; 13th edition; Chapter 5; Membrane Potentials and Action Potentials

Salt concentration is increased beneath the myelin segments

Non gated ion channels are present beneath the segments of myelin

Membrane resistance is decreased beneath the segments of myelin

Voltage-gated sodium channels are concentrated at the nodes of Ranvier


Question: Normal QRS axis

Ans. (b) -30 to 110degRef: Ganong, 25th ed/p.524Normally, the QRS axis ranges from -30deg to +100degAxis more negative than -30deg is called left axis deviationAxis more positive than +100deg is called right axis deviation


Question: Hypercalcemia associated with malignancy is most often mediated by

Hypercalcemia is an abnormally high level of calcium in the blood, usually more than 10.5 milligrams per deciliter of blood.parathyroid hormone-related peptide (PTHrP), a hormone that can be produced by tumors, especially of the squamous cell type; massive overproduction can lead to hypercalcemia and other manifestations of hyperparathyroidism. PTHrP exes a biologic action similar to that of parathyroid hormone (PTH), acting through the same receptor, which is expressed in many tissues but most abundantly in kidney, bone, and growth plate cailage. Ref: Ganong&;s review of medical physiology; 24th edition; page no:-378

Parathyroid hormone related protein (PTHrP)


Question: Axonotmesis includes discontinuity in

Axonotmesis is a disruption of nerve cell axon, with Wallerian degeneration occurring below and slightly proximal to the site of injury. If axons and their myelin sheath are damaged, but Schwann cells, the endoneurium, perineurium and epineurium remain intact, it is called axonotmesis.


Question: Conversion of chondrocyte into osteogenic cells is caused by

Growth hormone (GH) any of several related polypeptide hormones secreted by the anterior lobe of the pituitary gland that directly influences protein, carbohydrate, and lipid metabolism and controls the rate of skeletal and visceral growth; their secretion is in pa controlled by the hypothalamus.Ref: Ganong&;s review of medical physiology; 24th edition; page no: 327


Question: Natural acclimatization in high altitude is due to

(Decreased oxygen level): (650-Ganong-24th edition, 488-89- A.KJain 5th, 529-30- Guyton 12th)* Hypoxia in permanent residents at high altitude is called "acclimatization" at high altitude* Mechanism|Arterial pO2|Stimulate peripheral chemoreceptors||Pulmonary ventilation|CO2 washout|l Alveolar pCO2|||H+ concentration in blood (Alkalosis) and this should inhibit the respiration Differences between 'High Altitude Native' and Newcomer to High Altitude1. Increase in pulmonary ventilationMore therefore(a) Chest become enlarged (barrel shape)(b) Alveolar ventilation is more(c) FRC is moreLess therefore(a) Chest is smaller in size(b) Alveolar ventilation is less(c) FRC is less2. Response to hypoxic stimulationMore, therefore, hypocapenic alkalosis is lessLess3. Urine reactionAlkalineAcidic4. Affinity of haemoglobin for O2Less, therefore, more O2 is released from haemoglobinMore , therefore body tissue suffers from hypoxia,5. RBC countHigher, therefore PCV increases,Because of polycythemia, these individuals have red cheeksLow6. Organ vascularityMoreLess7. Mitochondria and myoglobin content of muscleHighLow8. Diffusion capacity of lung for O2MoreLess

Increase the chest size and decrease the abdominal circumference/accommodate


Question: Energy producing enzymes are located in

In mitochondria, enzymes for energy metabolism and protein synthesis can be found.


Question: The following acute respiratory response to ascent to high altitude, there is normalization of blood pH. The mechanism is

The lung response to acute altitude exposure is mainly hyperventilation which, together with elevated hea rate, aims at achieving an adequate supply of oxygen to the tissues. At rest, ventilation increases by firstly increasing the tidal volume, at least up to 3500 m. Ref: guyton and hall textbook of medical physiology 12 edition page number:365,376,377

Increased erythropoesis leads to increased buffering by hemoglobin

Increased excretion of HCO3 - by the kidneys


Question: Golgi tendon apparatus conveys message to cns, depends upon

The Golgi tendon organ (GTO) (also called Golgi organ, tendon organ, neurotendinous organ or neurotendinous spindle) is a proprioceptive sensory receptor organ that senses changes in muscle tension. It lies at the origins and inseion of skeletal muscle fibers into the tendons of skeletal muscle. It provides the sensory component of the Golgi tendon reflex.(Ref: Ganong&;s review of medical physiology 23rd edition Page no: 162 )


Question: Ejection fraction is about

The ejection fraction, the percent of the end-diastolic ventricular volume that is ejected with each stroke, is about 65%. The ejection fraction is a valuable index of ventricular function.


Question: In caissons, disease pain in joint is because of

Caisson's disease has many synonyms : as:- Bends - Decompression sickness - Diver's paralysis - Dysbarism.It occurs in divers, compressed air is taken in order to match the pressures at deep sea.The air contains Nitrogen in almost 70 % of the mixture.At high pressures in the sea, the pressure over the body is balanced by the compressed air delivered to the lungs and the N2 stays dissolved in the tissues, more in fat than in other compaments.But if the diver ascends very quickly then the N2 is conveed into its gaseous form as the pressure outside the body drops down to 1 atm. (760 mm Hg), at first, they are smaller bubbles which later coalesce and progressively larger vessels are affected.Tissue ischemia and sometimes tissue death is the result.Coronaries getting blocked, cause myocardial damage.Most people with bends have joint pains and muscles of the arms and legs affecting 85-90%.Ref: Ganong 22nd Ed/ Pg 695, Guyton 11th Ed/Pg 549,548


Question: Wernicke's area is located in

Wernicke's area (area 22) is located in superior temporal gyrus behind area 41. It is concerned with comprehension i.e. interpretation and understanding of auditory and visual information. The Wernicke's area sends information arcuate fasciculus to the Broca's area, where detailed and coordinated pattern for vocalization occurs. Ref: guyton and hall textbook of medical physiology 12 edition page number:841,842,843


Question: Vibration sense is carried by


Question: Anatomical dead space of normal lung is


Question: Dose of atropine for premedication per kg body weight is

0.01 mg Doses of atropine: For premedication: 0.01 mg/kg. Along with neostigmine for preventing muscarinic side effects: 0.02 mg/kg. Vagolytic dose: 2 mg (0.04 mg/kg).


Question: In general systolic BP in young females is less than that in the males of same age due to

In females before menopause SBP is 4-5 mmhg less than that in the males of same age .After menopause SBP is 4-5 mmhg more than males of same age. This effect may be due to oestrogen which prevents atherosclerosis. Ref: page number 349 Textbook of physiology Volume 1 AK Jain 7th edition

Oestrogen which prevents atherosclerosis


Question: In infants, defecation often follows a meal. The cause of colonic contractions in this situation is

(Gastrocolic reflex) (511- Ganong) (477- Ganong 23rd)* Distention of the stomach by food initiates contactions of the rectum and , frequently a desire to defecate. The response is called the Gastrocolic reflex* Some evidence that it is due an action of gastrin on the colon and is not neurally mediated* When food leaves the stomach, the cecum relaxes and the passage of chyme through the ileocecal valve increases (Gastroileal reflex). This is presumably a vagal reflex.


Question: The parvocellular pathway from lateral geniculate nucleus to visual coex is most sensitive for the stimulus of

From the lateral geniculate nucleus, a magnocellular pathway and a parvocellular pathway project to the visual coex. The parvocellular pathway, from layers 3-6, carries signals for color vision, texture, shape, and fine detail. The parvocellular pathway also carries color opponent data to the deep pa of layer 4.Ref: Ganong's Review of Medical Physiology, Twenty-Third Edition


Question: Broca's motor speech area is present in

Broca&;s area 44 is in the frontal lobe immediately in front of the inferior end of motor coex ( which is inferior frontal gyrus). Ref: Ganong&;s review of medical physiology;23rd edition; pg:297


Question: TSH on surface receptor uses second messenger as

Thyroid-stimulating hormone (TSH) is a hormone secreted by the pituitary gland that controls the release of T3 and T4 by the thyroid gland.The thyrotropin receptor (or TSH receptor) is a receptor (and associated protein) that responds to thyroid-stimulating hormone(also known as "thyrotropin") and stimulates the production of thyroxine (T4) and triiodothyronine (T3). The TSH receptor is a member of the G protein-coupled receptor superfamily of integral membrane proteins and is coupled to the Gs protein.Upon binding circulating thyrotropin, a G-protein signal cascade activates adenylyl cyclase and intercellular levels of cAMP rise .cAMP activate all functional aspects of the thyroid cell, including iodine pumping; thyroglobulin synthesis, iodination, endocytosis and proteolysis; thyroid peroxidase activity; and hormone release.Ref: Ganong&;s review of medical physiology;24th edition; page no-302


Question: Monoamine neurotransmitter in brains is

There are three main classes of chemical substances that serve as neurotransmitters and neuromodulators: small molecule transmitters large-molecule transmitters gas transmitters. Small molecule transmitters include amino acids (eg, glutamate, g-aminobutyric acid , and glycine, acetylcholine, monoamines (eg, norepinephrine, epinephrine, dopamine, and serotonin. Large-molecule transmitters include neuropeptides such as substance P, enkephalin, and vasopressin. Neuropeptides are often co-localized with one of the small-molecule neurotransmitters Ref: Ganong's Review of Medical Physiology 26th edition


Question: Action of progesterone is

Progesterone, hormone secreted by the female reproductive system that functions mainly to regulate the condition of the inner lining (endometrium) of the uterus. Progesterone is produced by the ovaries, placenta, and adrenal glands. Ref: guyton and hall textbook of medical physiology 12 edition page number:644,645,646

Increased sensitivity of uterus to oxytocin


Question: Excitable tissue at rest is least permeable to

Points to note
-        Concentration of ions

Na+ concentration higher in ECF
K+ concentration higher in ICF
Cl- concentration higher in ECF

-        K+ leak channels allow K+ to move from ICF to ECF

Na+ is prevented from entering the cell.

Thus diffusion is highest for K+, then Cl- and least for Na+, when the cell is at rest.


Question: The function of Carotid body is

Measures the change in PO2 in arterial blood

Measures the change in CO2 in arterial blood

Measures the change in CO2 in venous blood


Question: Gastric phase of gastric acid secretion is influenced by

The gastric secretions arise from glands in the wall of the stomach that drain into its lumen, and also from the surface cells that secrete primarily mucus and bicarbonate to protect the stomach from digesting itself, as well as substances known as trefoil peptides that stabilize the mucus-bicarbonate layer. The glandular secretions of the stomach differ in different regions of the organ. The most characteristic secretions derive from the glands in the fundus or body of the stomach. There are three primary stimuli of gastric secretion, each with a specific role to play in matching the rate of secretion to functional requirements. Gastrin is a hormonethat is released by G cells in the antrum of the stomach both in response to a specific neurotransmitter released from enteric nerve endings, known as gastrin-releasing peptide (GRP, or bombesin) and also in response to the presence of oligopeptides in the gastric lumen. Gastrin is then carried through the bloodstream to the fundic glands, where it binds to receptors not only on parietal (and likely, chief cells) to activate secretion but also on so-called enterochromaffin-like cells (ECL cells) that are located in the gland and release histamine. Histamine is also a trigger of parietal cell secretion, binding to H2 histamine receptors. Finally, parietal and chief cells can also be stimulated by acetylcholine, released from enteric nerve endings in the fundus. During the cephalic phase of gastric secretion, secretion ispredominantly activated by vagal input that originates from the brain region known as the dorsal vagal complex, which coordinates input from higher centers. Vagal outflow to the stomach then releases GRP and acetylcholine, thereby initiating secretory function. However, before the meal enters the stomach, there are few additional triggers and thus the amount of secretion is limited. Once the meal is swallowed, on the other hand, meal constituents trigger substantial release of gastrin and the physical presence of the meal also distends the stomach and activates stretch receptors, which provoke a "vago-vagal" as well as local reflexes that fuher amplify secretion. The presence of the meal also buffers gastric acidity that would otherwise serve as a feedback inhibitory signal to shut off secretion secondary to the release of somatostatin, which inhibits both G and ECL cells as well as secretion by parietal cells themselves. This probably represents a key mechanism whereby gastric secretion.REF: GANONG&;S REVIEW OF MEDICAL PHYSIOLOGY, KIM BARRETT, SCOTT BOITANO, SUSAN BARMAN, HEDDWEN BROOKSTWENTY THIRD EDITIONPAGE NO: 432,433


Question: The function of P cells of the kidney is

The principal cells reabsorb sodium and water from the lumen and secrete potassium ions into the lumen.


Question: Number of Golgi tendon organs per 100 muscle fibres

The Golgi organ (also called Golgi tendon organ, GTO, tendon organ, neurotendinous organ or neurotendinous spindle) is a proprioceptive sensory receptor organ that senses changes in muscle tension. It lies at the origins and inseion of skeletal muscle fibers into the tendons of skeletal muscle. It provides the sensory component of the Golgi tendon reflex.


Question: Breathing ceases upon destruction of the


Question: Concentration of methemoglobin to appears cyanosis


Question: Duration Of 2nd hea sound is

The second sound lasts about 0.12 s, with a frequency of 50 Hz. It is loud and sharp when the diastolic pressure in the aoa or pulmonary aery is elevated, causing the respective valves to shut briskly at the end of systole Second hea sound is due to sudden closure of semilunar valves at the end of systole. Ref: Ganong's Review of medical physiology 25th edition. Page: 542


Question: In the absence of vasopressin, the greatest fraction of filtered water is absorbed in the

Because the ratio of the concentration in tubular fluid to the concentration in plasma (TF/P) of the nonreabsorbable substance inulin is 2.5 to 3.3 at the end of the proximal tubule, it follows that 60–70% of the filtered solute and 60–70% of the filtered water have been removed by the time the filtrate reaches this point.


Question: Fat is maximum synthesized in

Fatty acid synthesis is the creation of fatty acids from acetyl-CoA and malonyl-CoA precursors through action of enzymes called fatty acid synthases. It is an impoant pa of the lipogenesis process, which - together with glycolysis - stands behind creating fats from blood sugar in living organisms.De Novo Synthesis in Humans In humans, fatty acids are formed predominantly in the liver and lactating mammary glands, and, to a lesser extent, the adipose tissue. Ref: Ganong&;s review of medical physiology - 24th edition; page no-26


Question: Oxygen carrying capacity of blood is largely determined by

The O2 delivery system in the body consists of the lungs and the cardiovascular system. O2 delivery to a paicular tissue depends on the amount of O2 entering the lungs, the adequacy of pulmonary gas exchange, the blood flow to the tissue, and the capacity of the blood to carry O2. The blood flow depends on the degree of constriction of the vascular bed in the tissue and the cardiac output. The amount of O2 in the blood is determined by the amount of dissolved O2, the amount of hemoglobin in the blood, and the affinity of the hemoglobin for O2.Ref: Ganong review of medical physiology 23rd edition Page no: 609


Question: Cell shape and physical structure is provided by

Microtubules are the largest cytoskeleton component. Cytoskeleton provides a structural framework for the cell. (REF TEXTBOOK OF MEDICAL PHYSIOLOGY GEETHA N 2 EDITION, PAGE NO - 9)


Question: Atrial depolarization in ECG is represented by


Question: Thromboxane A2 causes

Thromboxane A2 secreted by platelets promotes platelet aggregation and vasoconstriction Ref: Ganong's Review of Medical Physiology Twenty-Third Edition Page No:563

Vasodilatation and anti platelet aggregatory

Vasoconstriction and anti platelet aggregatory

Vasoconstriction and platelet aggregaion


Question: Hypoxemia independent of

Hypoxemia is a condition of decreased aerial po2.Ref: Ganong review of medical physiology 24th edition Page no: 649


Question: Least mineralocoicoid activity is seen in


Question: Somatosensory area I largest representation is for

Coical areas for sensation from trunk and back are small, whereas large areas are concerned with impulses from hand and pas of mouth. And from the figure 11-4 it is evident that area for hand is more than face. Ref: Ganong&;s review of medical physiology; 23rd edition; pg:175


Question: Amount of coronary flow per minute is

Total blood flow through various organs (whole organ)

Liver - 1500ml/min - 27.8% of cardiac output
Kidney - 1260ml/min - 23.3% of cardiac output
Skeletal muscle - 840ml/min - 15.6% of cardiac output
Brain - 750ml/min - 13.9% of cardiac output
Skin - 462ml/min - 8.6% of cardiac output
Heart - 250ml/min - 4.7% of cardiac output

Blood flow per unit mass in decreasing order –ml/100gm/min (Highest to lowest)

Kidney
Heart
Liver
Brain
Skin
Skeletal muscle


Question: Maximum prostaglandin secretion is seen in

Ans. is 'c' i.e., Seminal fluid"The concentrations in semen and mensural fluid probably reprent the highest concentrations of PGs found in human body" --www.reproductiveonline.org.


Question: Maximum blood in the body lies in

Maximum blood in the body lies in - veins and venules -64%.Ref: Guyton and hall 11th edition.


Question: "NO" is synthesized from

NO (nitric oxide):- Also called asEndothelium derived Relaxing Factor synthesized fromArginineby enzymeNOS(Nitric oxide synthase) in the endothelial cells Nitric oxide relaxes the smooth muscles of blood vessels The vasodilator - nitroglycerin also enters smooth muscle cells, where its metabolism also leads to the formation of NO. Activates enzymeGuanyl cyclase, which conves GTP to cyclic GMP, which causes relaxation of smooth muscle cells


Question: Not included in cerebellar nuclei

There are 4 deep nuclei in cerebellum: dentate, globose, emboliform, & fastigial nuclei. Ref: Ganong&;s review of medical physiology; 23rd edition; pg:255


Question: Dicrotic notch is caused by

Closure of aoic and pulmonary valve causes a characteristic notch called dicrotic notch or incisura in pulse wave tracing Ref : Ganong 25th ed/page 540


Question: A patient is able to recognise a person by name but not face. The lesion, in this case, is in

This condition is prosopagnosia, which occurs in the lesions of the inferior temporal lobe. In humans, storage and recognition of faces are more strongly represented in the right inferior temporal lobe in right-handed individuals (i.e., non-dominant inferior temporal lobe) Damage to this area can cause prosopagnosia, the inability to recognise faces. Patients with this abnormality can recognise people by seeing their faces. The left hemispheres is also involved, but the role of te right hemisphere is primary. Ref : Ganong's Review of Medical Physiology 25th edition Pgno: 293


Question: Pressure on carotid sinus causes


Question: The bitter taste is mediated by the action of

Sweet- G protein coupled increased in cAMP causing closure of K+ channels.
Salt- Opening of amiloride sensitive Na+ channels
Sour- Increased intracellular H+ concentration causing closure of K+ channels
Bitter- G protein-coupled increase in intracellular Ca++ triggering neurotransmitter release.


Question: GFR is increased by

Atrial natriuretic peptide (ANP) a hormone involved in natriuresis and the regulation of renal and cardiovascular homeostasis. It is synthesized as a prohormone in the granules of the myocytes of the atrium and is released into the circulation in response to atrial dilation or increased intravascular fluid volume.Ref: Ganong&;s review of medical physiology; 24th edition; page no; 707


Question: The characteristic feature of apoptosis on light microscopy is

The nuclear chromatin is condensed or fragmented by light microscopy.(Ref: Textbook of PATHOLOGY HARSH MOHAN 6th Edition page no.48)


Question: Essential difference between serum and plasma is in content of

Ans: a (Protein) Ref: Ganong 22nd edp.543Serum = Plasma - (fibrinogen, clotting factors II, V, VIII).Serum has higher serotonin content because of breakdown of platelets during clotting.Normal plasma volume is about 5% of body weight, -3500 ml in 70 kg man.


Question: Modality that is lost on the ipsilateral side in Brown sequard syndrome is

In Brown sequard syndrome, a hemisection of the spinal cord results in
-        Sensory

Loss of Ipsilateral dorsal column sensations- Proprioception, vibration, fine touch, Kinesthesia.
Loss of contralateral lateral column sensations- Pain, temperature

-        Motor

Loss of ipsilateral corticospinal action- results in UMNL- Weakness, spasticity, Extensor plantar response.


Question: Sleep waves in hippocampal area is(MP 2000, AI 1998, KARNATAKA 2002, ASSAM 2002)

Ans. (b) Theta(Ref: Ganong, 25th ed/p.273)Theta wave#Frequency is 4-7Hz#Generated in hippocampus#Most commonly seen in children#Pathologically seen often in degenerative brain diseases


Question: Afferent of Cremasteric reflex includes

CREMASTERIC REFLEX:-Upon stroking the skin of upper pa of medial side of thigh, there occurs a reflex contraction of muscle. It can be seen as elevation and retraction of the testis.Afferent:- genitofemoral nerve.Efferent: genital branch for cremaster muscle.More brisk in children.In UMN lesions,above segment L1 the reflex is lost.{Reference: BDC 6E pages no.206}


Question: Distribution of blood flow in mainly regulated by

Aerioles are the major site of resistance to the blood flow and small change in their caliber cause large changes in total peripheral resistance, and thereby diastolic pressure is affected. Ref: Ganong's Review of medical physiology, 24th edition.Pg no. 570


Question: Maximum visual acuity in retina is present on

(B) Fovea centralis > Visual acuity, or resolving power, is the property of cones. To resolve detail, the eye's optical system has to project a focused image on the fovea, a region inside the macula having the highest density of cone photoreceptor cells (the only kind of photoreceptors existing on the fovea), thus having the highest resolution and best color vision.


Question: Vagal stimulation in hea decreases hea rate by


Question: Function of Golgi apparatus is

Organization of the Golgi is directed at proper glycosylation of proteins and lipids. There are more than 200 enzymes that function to add, remove, or modify sugars from proteins and lipids in the Golgi apparatus. Membranous vesicles containing newly synthesized proteins bud off from the granular endoplasmic reticulum and fuse with the cistern on the cis side of the apparatus. The proteins are then passed other vesicles to the middle cisterns and finally to the cistern on the trans side, from which vesicles branch off into the cytoplasm.(REF: GANONG'S REVIEW OF MEDICAL PHYSIOLOGY 23rd EDITION page no.42)


Question: Excitatory ncurotransmitter in brain is

(A) Ach # Acetylcholine# ACETYCHOLINE is distributed throughout the CNS, with high concentrations in the cerebral cortex, thalamus, and various nuclei in the basal forebrain.> Ach was the first neurotransmitter discovered and is the major neurotransmitter in the peripheral nervous system,> Ach is excitatory in contract to monoamine neurotransmitters which are nearly always inhibitory.> Primary monoamine neurotransmitters are dopamine, norepinephrine and serotonin.> Dopamine and epinephrine are primarily inhibitory neurotransmitters that produce arousal.


Question: HCl secretion is stimulated bya)  Secretinb) Somatostatinc) Histamined) Gastrine) VIP

HCl secretion
-        Stimulated by
o   Acetylcholine- Cephalic and Gastric phase (Vaso vagal reflex)
o   Gastrin- Gastric and Intestinal phase
o   Histamine
-        Inhibited by
o   Acid (low pH)
o   Somatostatin
o   Secretin
o   Cholecystokinin
o   GIP
o   VIP


Question: Acetylcholine acting on nicotinic receptors produces

Acetylcholine acting at motor and causes muscle contraction Ref: guyton and hall textbook of medical physiology 12 edition page number:76,77,78


Question: Excitatory post synaptic potential is

EPSP: Depolarisation of post synaptic membrane by opening of Na+ or Ca2+ channels
IPSP : Hyperpolarisation of post synaptic membrane by opening of Cl- or K+ channels

Depolarisation of post synaptic membrane by opening of K+ channels

Hyperpolarisation of post synaptic membrane by opening of Cl- channels

Depolarisation of post synaptic membrane by opening of Ca2+ channels

Hyperpolarisation of post synaptic membrane by opening of Na+ channel


Question: Discharge from baroreceptor cause inhibition of

Ans. (b) Rostral ventrolateral medulla (RVLM)Ref: Ganong, 25th ed/p.590Baroreflex mechanismIn simple terms, "increased baroreceptor discharge inhibits the tonic discharge of sympathetic nerves and excites the vagal innervation of the heart"


Question: In a standard Electrocardiogram, an augmented limb lead measures the electrical potential difference between

Augmented limb leads are recordings between one limb and the other two limbs Augmented limb leads, designated by the letter a (aVR, aVL, aVF), are generally used Ref: Ganong's Review of Medical Physiology Twenty-Third Edition Page No:495 aVR: b/w right arm (+electrode)and left arm+left leg(-electrode) aVL: b/w the left arm(+electrodes) and right arm+left leg(-electrode) aVF: b/w the left foot (+electrode)and right arm+left arm(-electrode) Vector of augmented limb lead=3/2 vector of unaugmented limb lead.


Question: Characteristic feature of apoptosis

Reference: Robbins Basic Pathology, 9th edition Page no: 18 Apoptosis is a pathway of cell death in which cells activate enzymes that degrade the cells' own nuclear DNA and nuclear and cytoplasmic proteins. Fragments of the apoptotic cells then break off, giving the appearance that is responsible for the name (apoptosis, "falling off"). The plasma membrane of the apoptotic cell remains intact, but the membrane is altered in such a way that the cell and its fragments become avid targets for phagocytes. The dead cell and its fragments are rapidly cleared before cellular contents have leaked out, so apoptotic cell death does not elicit an inflammatory reaction in the host.


Question: Milk is stored before ejection in

Lactiferous ducts one of the ducts, numbering 15-20, which drain the lobes of the mammary gland; they open at the nipple.Ref: Ganong&;s review of medical physiology;24th edition; page no:-416


Question: Equilibrium potential of K+

Equilibrium potential of K+ is -90mV.(Ref: Textbook of physiology AK JAIN 4th edition page no.34)


Question: Higher hematocrit in venous blood than in arterial blood is due to

In venous blood, Cl- moves into RBC which results in fluid shift into RBC. This results in higher hematocrit.


Question: The physiological effect in unacclimatised person suddenly exposed to cold is

To preserve the core body heat in cold conditions, the flow of blood is decreased in the periphery (skin) by vasoconstriction. This prevents loss of heat.


Question: Ovulation is associated with sudden rise in

Ovulation is associated with LH surge Ref: guyton and hall textbook of medical physiology 12 edition page number:641,642,643


Question: Pleural pressure positive in

During active expiration, the abdominal muscles are contracted to force up the diaphragm and the resulting pleural pressure can become positive. Positive pleural pressure may temporarily collapse the bronchi and cause limitation of air flow Ref: guyton and hall textbook of medical physiology 12 edition page number:316,317,318


Question: Predominant cation of intracellular fluid

K+ concentration in I.C.F is 155 mEq/L of H2O.(Ref: Textbook of physiology AK Jain 5th edition page no.26 table 1.3.3)


Question: RMP of the neuron is

Resting membrane potential (RMP) - It is the potential difference between inside and outside of the membrane of a cell at a resting state.
RMP is maintained by K+ ion. The value for RMP varies for different kinds of tissues.
RMP of various tissues are given below RMP of a neuron is: -70 mV, RMP of cardiac muscle: —90 mV, RMP of skeletal muscle: -90 mV, RMP of smooth muscle: -50 mV. Note: RMP is maintained by K+ ion. RMP is close to isoelectric, the potential of Cl–  Changes in the external K+ concentration affect the RMP Changes in the external Na+ concentration affect the action potential and not the RMP


Question: Volume receptors are

Volume receptors are low-pressure receptors located in great veins, right and left atria, and pulmonary vessels.They are also called volume receptorsDue to the peculiarity of location of these receptors, they are affected by total cardiovascular output.Ref: Medical Physiology Indu Khurana 2015 edition page No:548

Stimulated by atrial systole and diastole

Stimulated by left ventricular contraction


Question: Slow IPSP in autonomic ganglia is generated bya) Nicotinic cholinergicb) Muscarinic cholinergicc) Dopamined) GnRHe) Adrenaline

Fast EPSP in autonomic ganglia are generated by Acetylcholine on nicotinic cholinergic receptors.
Slow EPSP in autonomic ganglia are generated by Acetylcholine on M1 muscarinic receptors.
Slow IPSP in autonomic ganglia are generated by Catecholamines (Dopamine, noradrenaline) on dopaminergic, α- adrenergic and M2 muscarinic receptors.


Question: Most peptide and protein hormones are synthesized as

Preprohormones are the gene products for most peptide and protein hormones. These are rapidly cleaved to form prohormones. POMC and propressophysin are two examples of specific prohormones.Ref: Guyton; 13th edition


Question: Anemic hypoxia is due to

Arterial PO2/ Dissolved oxygen is normal in anemic hypoxia, but the arterial oxygen content is low. This may be due to anemia, CO poisoning etc.


Question: PCT secretes

PCT secretes H+ into tubule thus helping in excretion . Ref: Ganong's review of medical physiology; 24th edition; page no: 685


Question: Osmolality of plasma is mainly contributed by


Question: Open faced nucleus in a cell signifies


Question: Decrease in contributing factor in chronic hypeension is associated with

Twofold increase in plasma TNF-alpha levels in pregnant rats resulted in a significant increase in aerial pressure (97 +/- 3.6 v 116 +/- 2.1 mm Hg, pregnant versus TNF-alpha pregnant, respectively, P < .05), but no significant change in urinary nitrite/nitrate excretion (22.0 +/- 1.9 v 20.8 +/- 2.5 micromol/24 h, pregnant versus TNF-alpha pregnant, respectively), a measure of whole-body NO production.


Question: The primary direct stimulus for excitation of central chemoreceptors regulating ventilation is

The main chemoreceptors involved in respiratory feedback are: Central chemoreceptors: These are located on the ventrolateral surface of medulla oblongata and detect changes in the pH of spinal fluid. Ref: guyton and hall textbook of medical physiology 12 edition page number:371,372,373


Question: Carbon monoxide poisoning is a type of

CO poisoning is often listed as a form of anemic hypoxia because the amount of hemoglobin that can carry O2 is reduced, but the total hemoglobin content of the blood is unaffected by CO. The affinity of hemoglobin for CO is 210 times its affinity for O2, and COHb liberates CO very slowly. Ref: Ganong&;s Review of medical physiology 25th edition. Page: 651


Question: Drug useful in chloroquine resistant malaria is

Mefloquine is effective against chloroquine resistant Plasmodium falciparum.


Question: Anatomical dead space is

Dead space is the volume of air that is inhaled that does not take pa in the gas exchange, because it either remains in the conducting airways or reaches alveoli that are not perfused or poorly perfused. In other words, not all the air in each breath is available for the exchange of oxygen and carbon dioxide Ref: guyton and hall textbook of medical physiology 12 edition page number: 324,325,326


Question: Involuntary contraction of a single motor unit is known as

Fasciculation : It is involuntary contraction of a single motor unit. It is visible grossly.
Fibrillation : It is spontaneous, repititive contraction of a single muscle fibre. It is not visible grossly.


Question: Minimum Ventilation perfusion ratio at base because

At Base, both Ventilation and Perfusion are good But Perfusion >> Ventilation. Hence Minimum Ventilation Perfusion ratio at base.


Question: For lymphogranuloma venereum the drug of choice is

Lymphogranuloma venereum causes potentially severe infections with possibly irreversible sequels if adequate treatment is not begun promptly. Early and accurate diagnosis is essential. Doxycycline is the drug of choice. Pregnant and lactating women should be treated with erythromycin or azithromycin. Ref kd tripati 6/e p570


Question: Resting membrane potential in ventricular myocardium

Ventricular cardiomyocyte membrane potential is about -90 mV at rest, which is close to the potassium reversal potential. When an action potential is generated, the membrane potential rises above this level in four distinct phases.


Question: A high plasma renin activity (PRA) is expected in patients

A high plasma renin activity (PRA) is present in patients who are taking angiotensin-conveing enzyme inhibitors.Renin is a proteolytic enzyme that is synthesized and stored in the juxtaglomerular (JG) apparatus, which consists of the juxtaglomerular cells (specialized myoepithelial cells) and the cells of the macula densa, located in the distal tubule. The JG cells surround the afferent aerioles of glomeruli in the kidneys. Once released, renin acts on angiotensinogen, which is synthesized in the liver, and conves it into the decapeptide angiotensin I. Angiotensin I is then enzymatically transformed into angiotensin II (All), an octapeptide, by conveing enzymes located in the kidney and the pulmonary vascular endothelium in the lungs. AII is a potent peripheral vasoconstrictor that directly acts on aeriolar smooth cells in the resistance vessels. In addition, it stimulates the efferent aerioles in the kidneys and has a negative feedback on renin release. All, along with the nonapeptide AIII, also stimulates the release of aldosterone from the zona glomerulosa in the adrenal coex. Aldosterone enhances the distal and early collecting tubule reabsorption of sodium in exchange for potassium and/or hydrogen ions.An angiotensin-conveing enzyme inhibitor, such as captopril, increases PRA because it is the negative feedback inhibition of All on renin release. This treatment is used to test for stimulation of renin release, paicularly in renovascular hypeension, in which there is an exaggerated increase in PRA.

Taking an angiotensin-conveing enzyme inhibitor


Question: Most common postprandial motility is seen in

It&;s sigmoid colon Tonic and phasic colonic motility and compliance of the transverse and sigmoid colon were therefore assessed using a combined barostat-manometry assembly in 22 healthy subjects. Measured colonic compliance was corrected by subtraction of the compliance of the closed barostat system. The mean (SEM) preprandial colonic volumes in the transverse and sigmoid colon were similar (150 (12) and 128 (13) ml, p = NS), corresponding to calculated mean (SEM) colonic diameters of 4.3 cm and 4.0 cm respectively. The mean increase in colonic tone postprandially was significantly greater in the transverse (24.1% (3.5)) than in the sigmoid colon (13.1% (3.0), p < 0.01). The mean increase in phasic contractility was significantly greater, however, in the sigmoid than in the transverse colon (1270 (210) and 425 (60) mm Hg/90 min respectively, p < 0.01). Compliance was greater in the transverse than sigmoid colon (7.6 (0.44) and 4.1 (0.15) ml/mm Hg, p < 0.001). The fasting volume of the colon was significantly correlated with the magnitude of the tonic response to the meal in the transverse and sigmoid colon (p < 0.001 for both). In conclusion, there are quantitatively different but qualitatively similar phasic and tonic responses to the meal in the two colonic regions. Differences in the viscoelastic and luminal dimensions may paly account for these differences in tonic responses.Ref: Ganong&;s review of medical physiology 23rd edition Page no: 475


Question: Average reproductive lifespan of ovum is

The egg cell, or ovum, is the female reproductive cell (gamete) in oogamous organisms. The egg cell is typically not capable of active movement, and average reproductive lifespan is about 12-24 hrs .it is much larger (visible to the naked eye) than the motile sperm cells. When egg and sperm fuse, a diploid cell (the zygote) is formed, which rapidly grows into a new organism.Ref: Ganong&;s review of medical physiology; 24th edition; page no: 406


Question: Normal Glucose level in CerebroSpinal Fluid (CSF) is

(B) 40-70 mg/dL REFERENCE VALUES FOR SPECIFIC ANALYTESCerebrospinal FluidReference RangeConstituentSI UnitsConventional UnitsOsmolarity292-297 mmol/kg water292-297 mOsm/LElectrolytesSodium137-145 mmol/L137-145 meq/LPotassium2.7-3.9 mmol/L2.7-3.9 meq/LCalcium1.0-1.5 mmol/L2.1-3.0 meq/LMagnesium1.0-1.2 mmol/L2.0-2.5 meq/LChloride116-122 mmol/L116-122 meq/LC02 content20-24 mmol/L20-24 meq/LPC026-7 kPa45--49 mmHgpH7.31-7.34 Glucose2.22-3.89 mmol/L40-70 mg/dLLactate1-2 mmol/L10-20 mg/dLTotal protein:Lumbar0.15-0.5 g/L15-50 mg/dLCisternal0.15-0.25 g/L15-25 mg/dLVentricular0.06-0.15 g/L6-15 mg/dLAlbumin0.066-0.442 g/L6.6-44.2 mg/dLIgG0.009-0.057 g/L0.9--5.7 mg/dLIgG index0.29-0.59 Oligoclonal bands (OGB)<2 bands not present in matched serum sample Ammonia15-47 pmol/L25-80 pg/dLCreatinine44-168 pmol/L0.5-1.9 mg/dLMyelin basic protein<4 mg/L CSF pressure 50-180 mmH2OCSF volume (adult)~150 mL Red blood cells00LeukocytesTotal0-5 mononuclear cells per L DifferentialLymphocytes60-70% Monocytes30-50% NeutrophilsNone > Normal CSF glucose range is 40-70 mg/dl (2.2-3.9 mmol/1).> Normal CSF glucose concentration is 2/3 of blood glucose concentration. If mean plasma glucose of 100 mg/dI is taken, then CSF glucose is 64 mg/dI, i.e. ratio of CSF glucose: plasma glucose = 0.64 (i.e., 2/3).> Cerebrospinal Fluid Chloride 120-130 mEq/l Glucose 50-75 mg/dl Proteins, total 15-40 mg/dl Albumin 8-30 mg/dl


Question: Lacis cells are seen in


Question: Half life of T4 is

Ans: D. 6 days(Ref: Ganong 25th/e p. 338-341; Understandings of medical physiology p. 7l9)Half life of T3 = 1 dayHalf life of T4 = 6 days.


Question: Erythropoietin in kidney is secreted by

Interstitial cells in paritubular capillaries releoses erythroportin in responce to hypoxia.

Interstitial cells in peritubular capillaries


Question: Structure passing through the opening marked 3 in the diaphragm is

Caval opening T8- The caval opening passes through the central tendon of the diaphragm. It contains the inferior vena cava and the right phrenic nerve. Ref anatomy B. D. Chourasia thorax p54


Question: Herring body is seen in

Herring bodies or neurosecretory bodies are structures found in the posterior pituitary. They represent the terminal end of the axons from the hypothalamus, and hormones are temporarily stored in these locations. They are neurosecretory terminals. The hypothalamohypophyseal tract is composed of axons of the large neurosecretory cells of the supraoptic and paraventricular nuclei of hypothalamus. The fibres of this tract are unmyelinated and pass to posterior lobe of pituitary through the infundibular stem of hypothalamus and form a series of dilated terminals known as Herring bodies, which come in contact with the capillary bed of neurohypophysis. The neurosecretory cells of supraoptic and paraventricular nuclei secrete vasopressin (ADH) and oxytocin. Ref: guyton and hall textbook of medical physiology 12 edition page number: 559,560,561


Question: GFR of a diabetic person is 90 ml/min. Blood glucose is 200 mg/dl. Calculate urinary glucose excretion rate if the Tm for glucose is 150 mg/min

Amount of filtered glucose = Plasma concentration of glucose X GFR = 90 ml/min X 200 mg /dl = 180 mg/min Rate of excretion of Glucose = Amount filtered - Tubular maximum Rate of excretion of Glucose = 180 mg/min -150 mg/min = 30 mg/min Ref : Ganong 25th ed/page 681


Question: CSF production per minute


Question: The frequency of first hea sound is

S1 is caused due to the closure of AV valves, it is long and soft with duration of 0.15s Ref: Ganong 25th ed/page 541


Question: The contribution of noncontractile muscle elements to total tension

“Active” tension is maximal at normal physiological muscle lengths. At point E, there is optimal overlap between actin and myosin filaments to support maximal crossbridge formation and tension development is maximum.


Question: Maximum concentration of sodium channel is at

At the node of Ranvier, Na channels are 2000 to 12000/sq micrometer of membrane(Ref: Textbook of physiology N Geetha 2nd edition page no.4)


Question: The tubuloglomerular feedback is mediated by

Signals from the renal tubule in each nephron feedback to affect filtration in its glomerulus. As the rate of flow through the ascending limb of the loop of Henle and first pa of the distal tubule increases, glomerular filtration in the same nephron decreases, and, conversely, a decrease in flow increases the GFR. This process, which is called tubuloglomerular feedback, tends to maintain the constancy of the load delivered to the distal tubule. The sensor for this response is the macula densa. The amount of fluid entering the distal tubule at the end of the thick ascending limb of the loop of Henle depends on the amount of Na+ and Cl- in it. The Na+ and Cl- enter the macula densa cells the Na-K-2Cl cotranspoer in their apical membranes. The increased Na+ causes increased Na, K ATPase activity and the resultant increased ATP hydrolysis causes more adenosine to be formed. Presumably, adenosine is secreted from the basal membrane of the cells. It acts adenosine A1 receptors on the macula densa cells to increase their release of Ca2+ to the vascular smooth muscle in the afferent aerioles. This causes afferent vasoconstriction and a resultant decrease in GFR. Presumably, a similar mechanism generates a signal that decreases renin secretion by the adjacent juxtaglomerular cells in the afferent aeriole, but this remains unsettled. Ref: Ganong&;s review of medical physiology,23rd edition,page no: 651,652

Sensing of Na+ concentration in the macula densa

Sensing of Cl+ concentration in macula densa

Sensing NaCl concentration in the macula densa

Opening up of voltage gated Na+ channels in afferent aeriole


Question: Plateau phase of ventricular muscle is d/t opening of

Ca2+ influx through more slowly opening Ca2+ channels produces the plateau phaseThe initial depolarization is due to Na+ influx through rapidly opening Na+ channels Repolarization is due to net K+ efflux through multiple types of K+ channels


Question: Stretch reflex of the bladder is integrated at

The bladder smooth muscle has some inherent contractile activity; however, when its nerve supply is intact, stretch receptors in the bladder wall initiate a reflex contraction that has a lower threshold than the inherent contractile response of the muscle. Fibers in the pelvic nerves are the afferent limb of the voiding reflex, and the parasympathetic fibers to the bladder that constitute the efferent limb also travel in these nerves. The reflex is integrated into the sacral portion of the spinal cord.


Question: Arteriole is

Arterioles regulate the distribution of blood flow by altering their diameter to increase or decrease the peripheral resistance as required.


Question: Glucose absorption from intestine occurs by

Ans. d (Secondary active transport). (Ref. Guyton, Physiology, 10th ed., 773)# In GI membrane and in renal tubules, glucose is transported by the mechanism of active sodium-glucose co-transport while at all other tissue cells glucose is transported by facilitated diffusion.# Glucose as such cannot diffuse through the pores of cell membrane, as max molecular wt. of glucose is 180.TRANSFER OF MATERIAL AND INFORMATION ACROSS MEMBRANES# Cross-membrane movement of small molecules- Diffusion* Passive AND Facilitated- Active transport* Primary active transport AND Secondary active transport# Cross-membrane movement of large molecules- Endocytosis* Fluid-phase endocytosis (random and nondirected)* Receptor-mediated endocytosis (selective and occurs in coated pits lined with clathrin)- Exocytosis# Signal transmission across membranes- Cell surface receptors* Signal transduction (eg, glucagon -cAMP)* Signal internalization (coupled with endocytosis, eg, the LDL receptor)- Movement to intracellular receptors (steroid hormones; a form of diffusion)# Intercellular contact and communicationSome properties of ion channels# They are composed of transmembrane protein subunits.# Most are highly selective for one ion; a few are nonselective.# They allow impermeable ions to cross membranes at rates approaching diffusion limits.# They can permit ion fluxes of 106-107/s.# Their activities are regulated.# The two main types are voltage-gated and ligand-gated.# They are usually highly conserved across species.# Most cells have a variety of Na+, K+, Ca2+, and CI- channels.# Mutations in genes encoding them can cause specific diseases.# Their activities are affected by certain drugs.


Question: Cushing's phenomenon is

Cushing reflex tends to restore the blood flow to the medulla. Over a considerable range, the blood pressure rise is propoional to the increase in intracranial pressure. The rise in blood pressure causes a reflex decrease in hea rate the aerial baroreceptors. This is why bradycardia rather than tachycardia is characteristically seen in patients with increased intracranial pressure. Ref: Ganong&;s Review of medical physiology 25th edition. Page:593


Question: ESPS is due to

Ans. (c) Na+ efflux(Ref: Ganong, 25th ed/p.122)Excitatory Post Synaptic Potentials (EPSP)#Produced if the neurotransmitter released at the synapse is excitatory#The excitatory transmitter opens mainly Na+ ion channels producing depolarization


Question: Metaerioles, vessels interposed between aerioles and capillary beds.

The proximal poion of a central channel is known as a metaeriole, whereas its distal poion is the thoroughfare channel. Blood from metaerioles may enter the capillary bed if their precapillary sphincters are relaxed. If the precapillary sphincters of metaerioles are constricted, blood bypasses the capillary bed and flows directly into thoroughfare channels and from there into a venule.

Function to control blood flow into aerioles.

Receive blood from thoroughfare channels

Possess a complete layer of smooth muscle cells in their tunica media.


Question: Calculate the minute ventilation from the spirogram assuming the respiratory rate as 12/min

Ans. (d) 6L/min(Ref: Guyton, 13th ed.P.503)Minute ventilation = tidal volume x respiratory rateHere tidal volume is 500 ml (in the graph, it is seen as 3 L to 3.5 L)So, Minute ventilation =500x12=6L/min


Question: Sho term BP regulation exeed through kidney by

Vasopressin is often called the antidiuretic hormone (ADH). It increases the permeability of the collecting ducts of the kidney, so that water enters the hypeonic interstitium of the renal pyramids. The urine becomes concentrated, and its volume decreases. The overall effect is, therefore, retention of water in excess of solute; consequently, the effective osmotic pressure of the body fluids is decreased.Ref: Ganong&;s Review of medical physiology 25th edition. Page: 696


Question: O2 delivery to tissue is decreased by


Question: A patient is on low calcium diet for 8 weeks. Following increases to maintain serum calcium levels

Parathyroid hormone (PTH), also called parathormone or parathyrin, is a hormone secreted by the parathyroid glands that is impoant in bone remodeling, which is an ongoing process in which bone tissue is alternately resorbed and rebuilt over time.Ref: Ganong&;s review of medical physiology: 24th edition; page no: 377


Question: The mechanism responsible for sustained vascular smooth muscle contraction is

Latch bridge mechanism: - Once smooth muscle has developed full contraction, the amount of continuing excitation can usually be reduced to far less than the initial level even though the muscle maintains its full force of contraction. Fuher the energy consumed to maintain contraction is often miniscule, sometimes as little as 1/ 300 the energy required for comparable sustained skeletal muscle contraction. This mechanism is k/a 'latch' mechanism. The impoance of latch mechanism is that it can maintain prolonged toxic contraction in smooth muscle for hours with little use of energy. Little continued excitatory signal is required from nerve fibres or hormonal source.

Sustained calcium release from SERCA pump


Question: K+ secretion from the loop of Henle is decreased by

Potassium-sparing diuretics act in the collecting tubule to inhibit Na+ reabsorption and K+ excretion. Spironolactone is a synthetic steroid that antagonizes aldosterone at intracellular cytoplasmic receptor sites. The spironolactone-receptor complex is inactive. That is, it prevents translocation of the receptor complex into the nucleus of the target cell and, therefore, it cannot bind to DNA. This results in a failure to produce proteins that are normally synthesized in response to aldosterone. These mediator proteins normally stimulate the Na+/K+-exchange sites of the collecting tubule. Thus, a lack of mediator proteins prevents Na+ reabsorption and, therefore, K+ and H+ secretion.Ref: Lippincott's Illustrated Reviews: Pharmacology, 5th edition, Page No: 286


Question: Golgi apparatus can be marked by

Markers of Plasma membrane - 5 '-Nucleotidase, Adenylyl cyclase, Na+ K+ATPase
Marker of Endoplasmic reticulum- Glucose-6-phosphatase
Markers of Golgi apparatus- GlcNAc transferase

Golgi mannosidase
Galactosyltransferase, Sialyltransferase

Marker of Mitochondria- ATP synthase, Glutamate dehydrogenase
Marker of Peroxisome- Catalase
Marker of Cytosol- LDH


Question: Inward flow of Na+ in heart leads to

Ans. (b) Action potential(Ref: Ganong, 25th ed/p.521)To be more precise, influx of sodium ions causes depolarization of ventricular action potential. It is usually seen in the form of a rapid upstroke (spike)


Question: Fetal hemoglobin has a higher affinity for oxygen due to

Make it very clear in mind that the higher affinity of fetal hemoglobin for oxygen is due to the low affinity of HbF for 2,3 - DPG (not due to decreased 2, 3-DPG concentration). HbF does not combine to 2, 3-DPG as avidly as adult hemoglobin.
"Fetal hemoglobin is left - shifted because it has a low affinity for DPG". — Principles of medical physiology
"It is worth noting that DPG does not combine with fetal hemoglobin. That is perhaps one reason why HbF has a greater affinity for oxygen than adult hemoglobin (HbF)". — Understanding of medical physiology
"Fetal hemoglobin binds less 2-3 DPG it has consequently a greater affinity for O2". _ Pediatric physiology
All other textbooks have mentioned the same thing.
So, the high affinity of HbF to O2 is due to the low affinity of HbF for 2, 3 DPG (and not due to decreased 2, 3-DPG concentration).
However, amongst the given options, option a is the best answer here because, although there is no decrease in concentration of 2, 3-DPG, because of low affinity for 2, 3-DPG, HbF behaves as if 2, 3-DPG levels are low.
"Fetal hemoglobin has considerably less affinity for 2, 3-DPG than does adult hemoglobin. In human blood, the affinity of fetal hemoglobin for 2, 3-DPG is only about 40% that of adult hemoglobin. This makes fetal hemoglobin behave as if 2, 3-DPG levels are low; therefore, the oxygen dissociation curve is shifted to the left". — Clinical physiology in childhood

Oxygen dissociation curve is shifted to right


Question: Escape phenomenon in mineralocorticoid excess occurs due to

Mineralocorticoid like action of cortisol


Question: Xanthinurate is a product/intermediate metabolite of

Conversion of tryptophan metabolite 3 hydroxy kynurenine to 2 hydroxy anthranilate is impaired in vitamin B6 deficiency? hence large amount of xanthinurate is formed.


Question: The most powerful feedback system for controlling plasma osmolarity and sodium concentration is

If osmotic pressure of the plasma is increased more than normal then the osmoreceptors are activated and ADH secretion increased. There's more receptors causes thirst and increase in the water intake. Daddy secretion causes water retention. This leads to dilution of ECF. Ref: page no 564 Textbook of physiology Volume 1 7th edition AK Jain


Question: Group B nerve fibres area) Sympathetic preganglionicb) Sympathetic postganglionicc) Parasympathetic preganglionicd) Parasympathetic post ganglionic

Types of nerve fibers
A fibers are fast fibers.
-        Aα- Somatic motor to extrafusal fibers of muscle spindle, proprioception
-        Aβ- Kinesthetic, pressure and touch
-        Aγ- Motor to intrafusal fibers of muscle spindle
-        Aδ-  Pain, temperature, touch and pressure
-        B fibers- Autonomic preganglionic (Myelinated)
-        C fibers- Pain, temperature, autonomic postganglionic (mainly sympathetic)


Question: The duration of a ventricular myocyte action potential is

The diagram depicts the relationship between the electrocardiogram (ECG) recorded on the surface of the body and the duration of a single ventricular myocyte action potential. The duration of the ventricular myocyte refractory period is nearly as long as the action potential, approximately 300 msec. The QRS complex of an ECG represents the electrical potential on the surface of the body produced by the wave of depolarization as it spreads through the ventricle and as each myocyte depolarizes (phase 0). The T wave represents ventricular repolarization (phase 3 in each myocyte). Note that the ST segment occurs during the plateau phase.

Approximately twice as long as the relative refractory period


Question: Node of Ranvier is seen in

A cross-section of a typical small nerve has many large nerve fibers that constitute most of the cross-sectional area. However, a more careful look revealsmany more small fibers lying between the large ones. The large fibers are myelinated, and the small ones are unmyelinated. The average nerve trunk contains about twice asmany unmyelinated fibers as myelinated fibers. The central core of the fiber is the axon, and the membrane of the axon is the membrane that actually conducts the action potential. The axon is filled in its center with axoplasm, which is a viscid intracellular fluid. Surrounding the axon is a myelin sheath that is often much thicker than the axon itself. About once every 1 to 3 millimeters along the length of the myelin sheath is a node of Ranvier. The myelin sheath is deposited around the axon by Schwann cells in the following manner: The membrane of a Schwann cell first envelops the axon. The Schwann cellthen rotates around the axon many times, laying down multiple layers of Schwann cell membrane containing the lipid substance sphingomyelin. This substance is an excellent electrical insulator that decreases ion flow through the membrane about 5000-fold. At the juncture between each two successive Schwann cells along the axon, a small uninsulated area only 2 to 3 micrometers in length remains where ions still can flow with ease through the axon membrane between the extracellular fluid and the intracellular fluid inside the axon. This area is called the node of Ranvier.Ref: Guyton and Hall textbook medical physiology, 13th edition.


Question: Exercise is also prescribed as an adjuvant treatment for depression. Most probably act by

Endorphins ("endogenous morphine") are endogenous opioid peptides that function as neurotransmitters. They are produced by the pituitary gland and the hypothalamus in veebrates during exercise, excitement, pain, consumption of spicy food, love and orgasm, and they resemble the opiates in their abilities to produce analgesia and a feeling of well-being.Ref: Ganong&;s review of medical physiology; 24th edition


Question: Chronaxie minimum in

Duration for which twice the rheobase strength has been applied to produce an action potential is called chronaxie. It is measure of excitability of the tissues. (REF TEXTBOOK OF MEDICAL PHYSIOLOGY GEETHA N 2 EDITION, PAGE NO - 30)


Question: The function of Phospholamban is

Phospholamban inhibits calcium pump on sarcoplasmic reticulum, thereby preventing uptake of Ca++ from the sarcoplasm.
When it is phosphorylated, the Ca++ channels open up and uptake of Ca++ is increased into the sarcoplasmic reticulum.

Transports calcium out of the mitrochondria

Inhibits Ca++ pump on sarcoplasmic reticulum


Question: Lipids are transferred from intestine to liver by


Question: Total lung capacity depends on

The extent to which the lungs will expand for each unit increase in transpulmonary pressure (if enough time is allowed to reach equilibrium) is called the lung compliance.The total compliance of both lungs together in the normal adult human averages about 200 milliliters of air per centimeter of water transpulmonary pressure. That is, every time the transpulmonary pressure increases 1 centimeter of water, the lung volume, after 10 to 20 seconds, will expand 200 milliliters.The total lung capacity is the maximum volume to which the lungs can be expanded with the greatest possible effo (about 5800 milliliters); It is equal tothe vital capacity plus the residual volume.Ref: Guyton; 13th edition; Chapter 38 Pulmonary Ventilation


Question: Compensatory mechanism in a patient with hypovolemic shock

In hypovolemic shock cutaneous blood flow is decreased because of vaso construction in skin Ref: guyton and hall textbook of medical physiology 12 edition page number:299,300,301


Question: In tetany hyperexcitability is due to

A i.e. Low Ca++ CausesT Na+ permeabilityA decrease in extra cellular Ca++ Concentration increases the excitability of nerve and muscle cells by decreasing the amount of depolarization necessary to initiate the change in Na+ & IC' conductance that produce the action potentialQ. In fact Ca++ needs to fall only 50% below the normal before spontaneous discharge occur from peripheral nerves, often causing tetany.The voltage gated calcium channels are slightly permeable to Na+ as well as Ca++;when they are activated both Na+ and Ca++ flow to interior of the fiber. When there is deficit of Ca2+ in ECF, Na+ channels become activated (opened) by very little change of membrane potential (from its very negative resting level to a less negative level). Therefore nerve fibers become highly excitable. Sometime discharging repetitively without provocation rather than remaining in resting stage.Conversely, an increase in ECF Ca++ stabilizes the membrane by decreasing excitability.


Question: HbA2 has

HbA2 contains 2 alpha and 2 delta chains.Adult Hb referred 5as HbA contains 2 alpha and 2 beta chains.Foetal Hb ie HbF contains 2 alpha and 2 gamma chains.Ref: Textbook of medical physiology by N Geetha, 2nd edition, page no. 74


Question: Destruction of anterior cerebellum in a decerebrate animal leads to

impaired coordination in the torso or arms and legs frequent stumbling an unsteady gait uncontrolled or repetitive eye movements trouble eating and performing other fine motor tasks slurred speech vocal changes headaches dizziness Ref : guyton and hall textbook of medical physiology 12 edition page number:781,782,783


Question: Postmoem caloricity is seen in

Postmoem caloricity A state in which the body temperature remains elevated--or even increases--for up to several hours after death.


Question: "Theta waves" are seen in

The first stage of sleep is characterized by theta waves, which are even slower in frequency and greater in amplitude than alpha waves. The difference between relaxation and stage 1 sleep is gradual and subtle. A person falling asleep first enters stage 1, the EEG begins to show a low-voltage, mixed-frequency pattern. A theta rhythm (4-7 Hz) can be seen at this early stage of slow-wave sleep. Theta and delta rhythms are normal during sleep, their appearance during wakefulness is a sign of brain dysfunction.Ref: Ganong's Review of Medical Physiology, Twenty-Third Edition


Question: P wave is absent in

It is characterized by totally irregular and rapid rateThere are no recognizable P waveRef: Medical Physiology for Under Graduate students Indu Khurana 2015 pg no: 202


Question: Facilitation of flexor muscle tone is by

Rubrospinal tract facilitates flexor muscle and inhibits extensor muscles.
Vestibulospinal tract facilitates extensor muscle of lower limb and inhibits flexors.


Question: Ejection fraction is

It is the volumetric fraction of fliud ejected from the chamber on each contraction. Normal is greater than 60%


Question: SI unit for measuring Blood pressure is


Question: Platelet helps in clot stabilisation by

Ans: b (Release of calcium) Ref Khurana text book of physiologyIf activated factor XIII is given the option you can go for that. Otherwise only correct answer is calcium. Thrombosthenin is involved in clot retraction.Platelet-associated factor XIII provides a means by which to promote clot stabilization and platelet interaction with proteins of the coagulation and fibrinolytic pathways.Fibrin stabilising factor (factor XIII) which is normally present in the plasma and also released from activated platelets is activated by thrombin to form XIIla but the XIIIa in the prescence of Ca2+ causes formation of covalent crosslinkages between fibrin threads, thus adding tremendous strength to the fibrin meshwork. The fibrin meshwork traps the remaining components of plasma and blood cells to form a solid mass called clotThrombomodulin is a thrombin binding protein produced by all endothelial cells except those in cerebral microcirculation.lt converts thrombin into protein C activator (AIPGME2007)Thrombasthenin is a contractile protein present in platelet involved in clot retraction and not in stabilizationActivated factor XIII will bind to the surface of activated platelets. These platelets then participate in cell-cell or cell-clot interactions, thereby increasing the local concentration of factor XIIIa.The platelet-associated factor Xllla may increase the amount of crosslinking in a fibrin clot, thereby contributing to the aging of the clot and the reduction in the degree of platelet binding. Clot resistance to fibrinolysis is enhanced by platelet factor XEIIa-mediated crosslinking of alpha 2-antiplasmin to fibrin. The binding of factor XIIIa to the platelet surface requires the activation of the platelet fibrinogen receptor, glycoprotein Ilb-IIIa.Thus, platelet-associated factor Xllla may be used as a marker of in vivo platelet activation. Since half of the factor XIII present in blood is provided by the platelets, it is not surprising that this form of factor XIII plays an important role in hemostasis.


Question: Increase blood flow to lungs cause

Other causes include obstructive sleep apnea, congenital hea disease, chronic hypoxemia, pulmonary thrombosis (blood clots), or left ventricular failure. ... Hemodynamically, PAH can be caused by increased right ventricular output, increased pulmonary systemic vascular resistance, or increased pulmonary venous pressure Ref: guyton and hall textbook of medical physiology 12 edition page number:311,312,313

No change in pulmonary vascular resistance

Initial increase followed by decrease in pulmonary vascular resistance


Question: Hyperthyroidism can be caused by


Question: 3rd heart sound is d/t

Occasionally a weak, rumbling third heart sound is heard at the beginning of the middle third of diastole.
A logical but unproven explanation of this sound is an oscillation of blood back and forth between the walls of the ventricles initiated by inrushing blood from the atria.
The reason the third heart sound does not occur until the middle third of diastole is believed to be that in the early part of diastole, the ventricles are not filled sufficiently to create even the small amount of elastic tension necessary for reverberation.
The frequency of this sound is usually so low that the ear cannot hear it, yet it can often be recorded in the phonocardiogram.


Question: During moderate exercise, blood flow to brain

Ans. c. Does not change Exercise During exercise there is a redistribution of cardiac outputQ Blood flow to the liver, kidneys and splanchnic circulation reducesQ. The blood flow to the exercising skeletal muscles and hea increases manifoldQ The blood flow to the brain remains unchangedQ.