Question: Action potential is produce by

(A) Sodium Influx # Action potential is due to opening of Na+ channels causing "Na+ influx"> As the membrane potential is increased, sodium ion channels open, allowing the entry of sodium ions into the cell. This is followed by the opening of potassium ion channels that permit the exit of potassium ions from the cell.> Inward flow of sodium ions increases the concentration of positively-charged cations in the cell and causes depolarization, where the potential of the cell is higher than the cell's resting potential.> Sodium channels close at the peak of the action potential, while potassium continues to leave the cell.> Efflux of potassium ions decreases the membrane potential or hyperpolarizes the cell.> For small voltage increases from rest, the potassium current exceeds the sodium current and the voltage returns to its normal resting value, typically -70 mV.> However, if the voltage increases past a critical threshold, typically 15 mV higher than the resting value, the sodium current dominates.> This results in a runaway condition whereby the positive feedback from the sodium current activates even more sodium channels. Thus, the cell "fires," producing an action potential


Question: While doing sigmoidoscopy, if the rectum is inflated with a gas increased peristalsis is seen in

Increase in intrarectal pressure initiates defecation reflex, so peristalsis increases in distal colon Ref: Ganong 25th ed/page 499


Question: NN Nicotinic acetylcholine receptors are present on

Nicotinic receptors are subdivided into those found at the; neuromuscular junction (NM) CNS and autonomic ganglia (NN) The NN receptors are comprised of only a and b subunits. Each a subunit has a binding site for acetylcholine, and binding of an acetylcholine molecule to each of them induces a conformational change in the protein so that the channel opens. NN receptors in the brain are located presynaptically on glutamate-secreting axon terminals Ref: Ganong's Review of Medical Physiology 26th edition

presynaptic glutamate-secreting axon terminals


Question: The following is an example of a primarily inhibitors amino acid

Glycine is the major inhibitory neurotransmitter in the brainstem and spinal cord, where it paicipates in a variety of motor and sensory functions. Glycine is also present in the forebrain, where it has recently been shown to function as a coagonist at the N-methyl-D-aspaate (NMDA) subtype of glutamate receptor. Ref: guyton and hall textbook of medical physiology 12 edition page number:64,65,66


Question: Neutrophil hypomotility syndrome is due to


Question: Gastrocolic reflex is related to

The gastrocolic reflex or gastrocolic response is one of a number of physiological reflexes controlling the motility, or peristalsis, of the gastrointestinal tract. Ref: guyton and hall textbook of medical physiology 12 edition:443,444,445


Question: During the cardiac cycle the opening of the aortic valve takes place at


Question: Secretions of GIT are controlled by

Secretions of GIT are controlled by the Meissner plexus. Ref: Ganong&;s Review of Medical Physiology 26th edition Pgno: 460


Question: Platelet function tested by

(A) Bleeding time # Most important screening tests of the primary hemostatic system are> Bleeding time (a sensitive measure of platelet function), and a platelet count.> Latter correlates well with the propensity to bleed. The normal platelet count is 150,000 to 450,000/mL of blood. As long as the count is > 100,000/mL, patients> are usually asymptomatic and the bleeding time remains normal.> Platelet counts of 50,000 to 100,000/mL cause mild prolongation of the bleeding time; bleeding occurs only from severe trauma or other stress.> Patients with platelet counts 50,000/pL have easy bruising, manifested by skin purpura after minor trauma and bleeding after mucous membrane surgery. Patients with a platelet count 20,000/pL have an appreciable incidence of spontaneous bleeding, usually have petechiae, and may have intracranial or other spontaneous internal bleeding


Question: Maroteaux Lamy syndrome characterized by deficiency of

Maroteaux-Lamy syndrome is mucopolysaccharidosis type VI, caused due to deficiency of N-acetylgalactosamine (arylsulphatase B).


Question: Tidal volume in a normal man at rest is

Normal tidal volume is 500 ml Ref: guyton and hall textbook of medical physiology 12 edition page number:324,325,326


Question: Blood pressure is defined as the product of

Blood pressure = Cardiac output  x Total peripheral resistance


Question: Each hemoglobin contains

Hemoglobin is a globular molecule made up of four subunits. Each subunit contains a heme moiety conjugated to a polypeptide. Heme is an iron-containing porphyrin derivative. The polypeptides are referred to collectively as the globin poion of the hemoglobin molecule. There are two pairs of polypeptides in each hemoglobin molecule. Reference: Ganong's review of Medical Physiology; 25th ed; Page: 557


Question: Myenteric plexus is present in

The myenteric plexus ( Auerbach&;s plexus), is situated between the outer longitudinal and middle circular muscle layers.The submucous plexus ( Meissner&;s plexus) is present between the middle circular layer and mucosa.Collectively these neurons constitute the enteric nervous system.It is also referred to as the " LITTLE BRAIN "(Ref: Ganong&;s Review of medical physiology, 23 rd edition, page 448)


Question: Airway resistance

If the air flow becomes turbulent during rapid respiration, the energy required to move the air is greater than when the flow is laminar.

Is increased if the lungs are removed and inflated with saline.


Question: Least clearance is for among these

Glucose is completely reabsorbed in proximal tubules. So its clearance is zero.


Question: Functions of limbic systema) Emotionb) Memoryc) Higher functiond) Planned motor activity

Main function of the limbic system is generation of emotions and the responses to those emotions, such as sexual behaviour, feeding behaviour, autonomic response, fear/rage, punishment/reward, memory, learning, vegetative and endocrine functions of hypothalamus.


Question: The half life of plasma albumin is approximately


Question: Consolidation of long term memory


Question: The fibers from the contralateral nasal hemiretina project to the following layers of the lateral geniculate nucleus

Look at figure 12-17 trace the nasal field of one eye it goes to layers 1,4,6 on contralateral side. Ref: Ganong&;s review of medical physiology;23rd edition; pg:194


Question: The best test for GFR is with

Properties of Inulin
-        Easily filtered by kidney
-        Not absorbed by kidney
-        Not secreted by kidney
-        Not metabolized by kidney
-        Not synthesized by kidney
-        Non-toxic
-        Easily measurable
Thus it is the best substance to use for measurement of GFR.


Question: Ovum is released due to

Ovulation-the discharge of a secondary oocyte from the Graafian follicle; in an adult woman, this normally occurs at intervals of about28 days and alternates between the two ovaries. As a rule, only one secondary oocyte is produced, but occasionally ovulation produces two or more; if more than one subsequently become feilized, the result may be multiple bihs, such as twinsEstrogen levels peak towards the end of the follicular phase. This causes a surge in levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). This lasts from 24 to 36 hours, and results in the rupture of the ovarian follicles, causing the oocyte to be released from the ovary the oviduct.Ref: Ganong&;s review of medical physiology; 24th edition


Question: If a single spinal nerve is cut, the area of tactile loss is always greater than the area of loss of painful sensation, because

Ans. (c) Degree of overlap of fiber carrying tactile sensation is much less(Ref: Ganong, 25th ed/p.160)The degree of overlap of fibers carrying pain is much greater than tactile sensationSo, the area of tactile loss is always greater for tactile sensation

Tactile information is carried by myelinated fast conduction fiber

Degree of overlap of fibers carrying tactile sensation is much less

In the primary sensory cortex tactile sensation is represented on a larger area


Question: Gap junctions are found in

Gap junction forms tunnels that join the cytoplasm of two cells. They permit the substance to pass from one cell to adjacent cells. It also helps in propagation of action potential from one cell to another. (REF: GANONG'S REVIEW OF MEDICAL PHYSIOLOGY)


Question: The plasma clearance value of glucose in a diabetes mellitus patient will be

Ans. (d) Greater than zero(Ref: Ganong, 25th ed/p.678)Diabetes mellitus is characterized by renal glycosuria. Glucose appears in urine. So, plasma clearance of glucose is greater than zero


Question: CO2 retention is seen in

CO2 retention seen in ventilatory failure Ref: guyton and hall textbook of medical physiology 12 edition


Question: The motivational — affect component of pain is carried by


Question: Skeletal muscle use the

The entry of glucose into skeletal muscle is increased during exercise in the absence of insulin by causing an insulin-independent increase in the number of GLUT 4 transpoers in muscle cell membranes.(REF.GANONG'S REVIEW OF MEDICAL PHYSIOLOGY 23rd EDITION page no.331)


Question: Macula densa is a pa of

The thick end of the ascending limb of the loop of Henle reaches the glomerulus of the nephron from which the tubule arose and nestles between its afferent and efferent aerioles. Specialized cells at the end form the macula densa, which is close to the afferent and paicularly the afferent aeriole. The macula, the neighboring lacis cells, and the renin-secreting juxtaglomerular cells in the afferent aeriole form the juxtaglomerular apparatus.Ref: Ganong&;s review of medical physiology,23rd edition, page: 641


Question: Inracellular concentration of K+ is

Ans. is 'd' i.e., 150 meq/L o Intracellular K+ concentration - 150 meq/Lo Extracellular K+ concentration - 4.5 - 5 meq/LComponentExtracellular fluid (ECF) (meq/1)Intracellular fluid (ICF) (meq/l)Na+K+C1-HCO3-Mg+2Ca+2PO4-21425.5103281[?]22[?]5414150410580 0001 75Protein (organic anion)5 (2g%)40 (16g %)

Cell Physiology and Intercellular Connections


Question: Best vehicle for oxygen is

97% of oxygen in blood combines with Hb and presence of Hb increases the oxygen carrying capacity of blood 70 fold.3% of blood os transpoed in dissolved form.ie 100 ml of pure blood contains 0.3ml of oxygen dissolved in plasma.Ref: Textbook of medical physiology by N Geetha, 2nd edition, page no. 241,242


Question: Pacemaker of respiration


Question: Depolarisation of atria on ECG is seen as

P wave shows atrial depolarizationQRS complex shows ventricular depolarization T wave shows ventricular repolarizationST segment represents the duration from the end of ventricular depolarization to the beginning of ventricular repolarizationRef: Textbook of medical physiology by N Geetha,2nd edition, page no. 136


Question: The approximate composition of proteins in cell membrane is

The cell membrane (also called the plasma membrane) envelops the cell and is a thin, pliable, elastic structure only 7.5 to 10 nanometers thick. It is composed almost entirely of proteins and lipids. The approximate composition is proteins, 55 percent; phospholipids, 25 percent; cholesterol, 13 percent; other lipids, 4 percent; and carbohydrates, 3 percent.(Ref: Guyton; 13th edition; Chapter 2 The Cell and Its Functions)


Question: The blood pressure regulatory system that is labeled as a buffer system is

Baroreceptor system opposes either increases or decreases in aerial pressure, it is called a pressure buffer system, and the nerves from the baroreceptors are called buffer nerves.Ref: Guyton and Hall textbook of medical physiology 13th edition. Page: 221


Question: Actin&;s active site is covered by

Tropomyosin molecules are long filaments located in the groove between the two chains in the action. In resting muscle, troponin I is bound to actin and tropomyosin and covers the sites wheremyosin heads interact with actin. The thick filaments, which are about twice the diameter of the thin filaments, are made up of myosin. Troponin is Ca2+-binding protein involved in contraction of skeletal muscle. Additional structural proteins that are impoant in skeletal muscle function include desmin. Desmin adds structure to the Z lines in pa by binding the Z lines to the plasma membrane(REF.GANONG'S REVIEW OF MEDICAL PHYSIOLOGY -23rd EDITION. Page No-94,96)


Question: Group A nerve fibers are most susceptible to

Pressure on a nerve can cause loss of conduction in large diameter motor,touch& pressure fibre ( ie group A fibre) ,while pain sensation (group c fibre) remains relatively intact. Ref: Ganong&;s Review of medical physiology;25th edition; pg: 95.


Question: 'Flare' in Triple response is mediated by

Lewis Triple response includes wheal, flare and red reaction.
Histamine when released causes capillary dilatation due to precapillary sphincter relaxation resulting in red reaction. Due to the dilatation, the gap between endothelial cells is widened, which leads to increased permeability and allows extravasation of fluid resulting in wheal. Axon reflex mediates arteriolar dilatation resulting in flare.


Question: A negatively charged molecule is filtered with more difficulty compared to a positive one because

Functionally, the glomerular membrane permits the free passage of neutral substances up to 4 nm in diameter and almost totally excludes those with diameters greater than 8 nm. However, the charges on molecules, as well as their diameters, affect their passage into Bowman's capsule. The negatively charged sialoproteins on the filtering membrane make it difficult for the negative paicles to pass through. The total area of glomerular capillary endothelium across which filtration occurs in humans is about 0.8 m 2Ref: Ganong&;s Review of Medical Physiology, 23rd edition, page no: 640

Presence of negatively charged sialoproteins on the filtering membrane

Positively charged proteins on filtering membrane


Question: The inverse stretch reflex

Golgi tendons organs are encapsulated stretch receptors located in the tendons that causes muscle relaxation when the tension becomes great enough. Golgi tendon organs, unlike the spindles, are in series with the muscle fibers. The tendon organ, like the primary receptor of the muscle spindle, has both a dynamic response and a static response Stretch reflex is monosynaptic while inverse stretch reflex is a disynaptic with a single interneuron inseed between the afferent and efferent limbs The spindle detects muscle length and changes in muscle length, whereas the tendon organ detects muscle tension Afferent for stretch receptor Ia, while for inverse stretch reflex: Ib

Is a monosynaptic reflex initiated by activation of the Golgi tendon organ

Is a disynaptic reflex activated on change in tension

Uses type II afferent fibres from the Golgi tendon organ


Question: 5 g mannitol was injected intravenously. 40% of mannitol is excreted. After equilibrium, plasma concentration of mannitol is 30 mg%. Calculate extracellular fluid volume.

The volume of water in different compament can be measured by volume of distribution principle (indicator dilution principle). Where v = Volume of fluid Q = Quantity of indicator given C = Concentration of the indicator e = The amount of indicator which has either been lost or metabolized 30 mg% = 30 mg/ 100 mL = 300 mg/ L = 0.3g/L Quantity of mannitol excreted = 5 * 40/100 = 2 g ECF volume = 5 - 2 / 0.3 = 3 / 0.3 = 10 L


Question: Descending motor tract responsible for rapid skilled movements.

Ans. is 'b' i.e., Rubrospinal tract o Pyramidal (corticospinal) tract and extrapyramidal tracts concerned with the muscles of the trunk and proximal portion of limbs (Le., the muscle mainly concerned with the postural control) occupy anterior white column of spinal cord and terminate in the medial ventral horn on the medial group of intemeurons. These tracts are collectively called medial pathways. Medial pathways include ventral (anterior) corticospinal tract, vestibulospinal tracts, reticulospinal tract and rubrospinal tract.o On the other hand, descending tracts concerned with distal muscles of the limb (i.e., those muscles which mediate fine skilled movements(A1 13)) occupy lateral white column and are called lateral pathways. Lateral pathways include lateral corticospinal tract and rubrospinal tracts.


Question: Dysmetria

Dysmetria refers to a lack of coordination of movement typified by the undershoot or overshoot of intended position with the hand, arm, leg, or eye. It is a type of ataxia. It is sometimes described as an inability to judge distance or scale. The actual cause of dysmetria is thought to be caused by lesions in the cerebellum or by lesions in the proprioceptive nerves that lead to the cerebellum that coordinate visual, spatial and other sensory information with motor control. Damage to the proprioceptive nerves does not allow the cerebellum to accurately judge where the hand, arm, leg, or eye should move. There are two types of cerebellar disorders that produce dysmetria, specifically midline cerebellar syndromes and hemispheric cerebellar syndromes. Midline cerebellar syndromes can cause ocular dysmetria, Hemispheric cerebellar syndromes cause dysmetria in the typical motor sense that many think of when hearing the term dysmetria. Ref: guyton and hall textbook of medical physiology 12 edition page number: 780,781,782


Question: Pancreatic juice rich in water & electrolytes, poor in enzymes are secreted by

The pancreatic juice contains enzymes that are of major impoance in digestion. Its secretion is controlled in pa by a reflex mechanism and in pa by the gastrointestinal hormones secretin and cholecystokinin(CCK). Secretion of pancreatic juice is primarily under hormonal control. Secretin acts on the pancreatic ducts to cause copious secretion of a very alkaline pancreatic juice that is rich in HCO3-and poor in enzymes. The effect on duct cells is due to an increase in intracellular cAMP. Secretin also stimulates bile secretion. CCK acts on the acinar cells to cause the release of zymogen granules and production of pancreatic juice rich in enzymes but low in volume. Its effect is mediated by phospholipase C.REF: GANONG&;S REVIEW OF MEDICAL PHYSIOLOGYKIM BARRETT, HEDDWEN BROOKS, SCOTT BOITANO, SUSAN BARMANPAGE NO:435,436


Question: Find out chronaxie and rheobase from the graph given below

Rheobase is the minimum stimulus strength that will produce a response. It corresponds to 0.3V Chronaxie is the minimum time duration for which a stimulus doubles the rheobase. Double the rheobase is 0.6V which corresponds to 0.2 msec.


Question: The primary cause for the development of shock following hemorrhage is

Hemorrhage is the most impoant cause of hypovolemic shock. There will be reduction in the venous return leading to a fall in cardiac output and BP. The severity of shock depends upon the rapidity of blood loss. Ref: Textbook of medical physiology by N Geetha, 3rd edition, page no. 204


Question: Pulmonary surfactant is secreted by

Ans. (b) Type II pneumocytes(Ref: Ganong, 25th ed/p.630)Surfactant is synthesized, secreted, and recycled by alveolar type II cells


Question: Not a cell adhesion molecule

Spectrin is a peripheral proteinAdhesive glycoproteins and adhesion receptors are structurally diverse molecules variously involved in cell-to-cell adhesion, linking cells to the ECM, and the interactions between ECM components. Prototypical adhesive glycoproteins include fibronectin (a major component of the interstitial ECM) and laminin (a major constituent of basement membrane). Integrins are representative of the adhesion receptors, also known as cell adhesion molecules(CAMs); the CAMs also include immunoglobulins, cadherins, and selectins.Ref: Robbin&;s; 9th edition; Chapter 1; The Cell as a Unit of Health and Disease


Question: The daily production of CSF is

(A) 550 ml# Cerebrospinal fluid (CSF)> Total volume of CSF is 150 mis.> Daily production is 550 mls/day so the CSF turns over about 3 to 4 times per day.> CSF is formed by the choroid plexus (50%) and directly from the walls of the ventricles (50%).> CSF flows through the foramens of Magendie & Luschka into the subarachnoid space of the brain and spinal cord.> It is absorbed by the arachnoid villi (90%) and directly into cerebral venules (10%).> Normal intracerebral pressure (ICP) is 5 to 15 mmHg.> Rate of formation of CSF is constant and is not affected by ICR> Absorption of CSF increases linearly as pressure rises above about 7 cms H20 pressure.> At a pressure of about 11 cms H20, the rate of secretion & absorption are equal.


Question: Bernoulli's principle states

Ans. (a) Sum of kinetic energy of flow and pressure energy is constantRef: Ganong, 25th ed/p.571Velocity of blood flow (kinetic energy) and the pressure (potential energy) are interrelated by the Bernoulli's principleBernoulli's principle#States that "The sum of the kinetic energy of flow and the potential energy--is constant"#According to the principle, the greater the velocity of flow in a vessel, the lower the#lateral pressure distending its walls to keep the total energy of the system constant

Low tones producing maximal stimulation at apex of cochlea

Magnitude of the sensation felt is proportionate to the intensity of stimulus

Force of contraction is proportional to the stretch of cardiac muscle


Question: Pontine transection leads to

Ans. (d) Decreased muscle tone(Ref: Ganong, 25th ed/p.242)Pontine transection leads to the loss of effects of Pontine reticulospinal tractNormal function of pontine reticulospinal tract - mediate excitatory effects. Excites gamma motor neurons to muscle spindles that maintains toneSo, there is decreased muscle tone


Question: Rapid infusion of insulin causes

B i.e. Hypokalemia Insulin promotes the transpo of K+ (potassium) and phosphate (PO4) into cells leading to hypokalemia and hypophosphatemiaQ, (i.e. L K+ & . Effect of Insulin on K+ and PO43- - Insulin increases the transpo of potassium (K+) from plasma into cells by stimulating the Na+-K+ - ATPase pumps in cell membranes of muscle, liver and adipocytes. This results in lowering of plasma (extracellular) K+ concentration i.e. hypokalemiaQ. - Infusions of insulin (and glucose) significantly lower the plasma K+ levels in normal individuals and are used for temporaty relief of hyperkalemia in patients with renal failure, waiting for dialysis. - Hypokalemia often develops when patients with diabetic acidosis are treated with insulin. - Insulin induces rapid entery of glucose into cells, a process which is followed by phosphorylation reaction in glycolytic pathway, lowering the intracellular concentration of inorganic phosphate, and therefore promotes phosphate (P03-4) entry into cells. This is how insulin 1/t hypophosphatemia (decrease plasma /ECF PO43-)


Question: Final stage of acid production by parietal cell

(B) H+-K+ ATPase pump > Gastric parietal cells are highly specialized for their unusual task of secreting concentrated acid. The cells are packed with mitochondria that supply energy to drive the apical H+,K+-ATPase, or proton pump, that moves H+ ions out of the parietal cell against a concentration gradient of more than a million-fold. At rest, the proton pumps are sequestered within the parietal cell in a series of membrane compartments known as tubulovesicles. When the parietal cell begins to secrete, on the other hand, these vesicles fuse with invaginations of the apical membrane known as canaliculi, thereby substantially amplifying the apical membrane area and positioning the proton pumps to begin acid secretion. The apical membrane also contains potassium channels, which supply the K+ ions to be exchanged for H+, and Cl- channels that supply the counterion for HCI secretio. The secretion of protons is also accompanied by the release of equivalent numbers of bicarbonate ions into the blood-stream, which are later used to neutralize gastric acidity once its function is complete.


Question: Function of vasopressin

Vasopressin- a hormone secreted by cells of the hypothalamic nuclei and stored in the posterior pituitary for release as necessary; it stimulates contraction of the muscular tissues of the capillaries and aerioles, raising the blood pressure, and increases peristalsis, exes some influence on the uterus, and influences resorption of water by the kidney tubules, resulting in concentration of urine.Ref: Ganong&;s review of medical physiology; 24th edition; page no:-303


Question: Most specific test to detect blood stains is

Spectroscopic test is the most specific for blood stains. Tests for blood stains Spectroscopy tests can give information about what chemical compounds and elements are present in a sample, whether ceain types of degradation have occurred in a sample, the amount and type of crystallinity present in the sample, to name a few uses. Ref ganong's review of medical physiology 25e


Question: A man not able to digest carbohydrate will be deficient in

Amylase helps in digestion of carbohydrates Ref: guyton and hall textbook of medical physiology 12 edition page number: 426,427,428


Question: Pressure diuresis is due to

As the pressure rises urine volume output is increased. This increased urinary output is the phenomenon of pressure diuresis. When GFR autoregulation is impaired, as often occurs in kidney disease, increases in aerial pressure can cause much larger increases in the GFR. The second effect of increased renal aerial pressure that raises urine output is that it decreases the percentages of the filtered loads of sodium and water that are reabsorbed by the tubules. The mechanisms responsible for this effect include a slight increase in peritubular capillary hydrostatic pressure, especially in the vasa recta of the renal medulla, and a subsequent increase in the renal interstitial fluid hydrostatic pressure. A third factor that contributes to the pressure natriuresis and pressure diuresis mechanisms is reduced angiotensin II formation.

Increase in peritubular hydrostatic pressure


Question: The most common site of ectopic pheochromocytoma is

Pheochromocytoma is a chromaffin cell tumor commonly located at adrenal medulla. Ectopic pheochromocytoma (EP) is considered as pheochromocytomalocated at extra-adrenal site, which usually lies at para-aoic region Ref ganong's review of medical physiology 25e


Question: Scotty Dog Sign is seen in

The Scottie dog sign refers to the normal appearance of the lumbar spine when seen on oblique radiographic projection. On oblique views, the posterior elements of the veebra form the figure of a Scottie dog with: the transverse process being the nose. the pedicle forming the eye. Ref essential ohopaedic maheshwari and mhaskar 6/e p240


Question: Motilin is secreted by cells ina) Stomachb) Duodenumc) Pancreasd)  Liver

Motilin secreted by
-        M cells of duodenal mucosa (Main)
-        Stomach

-        Colon


Question: The main excitatory neurotransmitter in the CNS is

Glutamate is the chief excitatory neurotransmitter in CNS.


Question: Glomerular filtration barrier does not permit

Glomerular filtration barrier - it has: - Glomerular capillary - has endothelial cells which are fenestrated Basement membrane Layer of epithelial cells (podocytes) Characteristics of the filtration barrier: - Has high filtration rate. Capillary endothelium is perforated by thousands of small holes called fenestrae. The basement membrane contains negatively charged sialo proteins; they repel negatively charged plasma proteins. Glomerular capillary has epithelial cells, these cells are not continuous but have long footlike processes (podocytes). Podocytes are separated by filtration slit pores, through which the filtrate moves. The epithelial cells also have negative charge. Pores of glomerular capillary are thought to be about 4 - 8 mm. (40- 80 angstroms) Filtration is both size selective & charge selective.


Question: Long term potentiation means

(A) Enhancement of signal transmission# LONG-TERM POTENTIATION (LTP): a long-lasting strengthening of the response of a postsynaptic nerve cell to stimulation across the synapse that occurs with repeated stimulation and is thought to be related to learning and long-term memory.> Long-term potentiation (LTP) is a long-lasting enhancement in signal transmission between two neurons that results from stimulating them synchronously.> It is one of several phenomena underlying synaptic plasticity, the ability of chemical synapses to change their strength.> As memories are thought to be encoded by modification of synaptic strength, LTP is widely considered one of the major cellular mechanisms that underlies learning and memory> NMDA receptor-dependent LTP exhibits several properties, including input specificity, associativity, cooperativity, and persisience.


Question: Ovarian follicles at bih in ovary are

An ovarian follicle is a roughly spheroid cellular aggregation set found in the ovaries. It secretes hormones that influence stages of the menstrual cycle. Women begin pubey with about 200,000 to 400,000 follicles, each with the potential to release an egg cell (ovum) at ovulation for feilization. These eggs are developed only once every menstrual cycle.Ref: Ganong&;s review of medical physiology;24th edition; page no:-403


Question: Increase in threshold level on applying subthreshold, slowly rising stimulus is known as

Accommodation- Slow rising subthreshold stimulus failing to produce action potential even when the normal threshold levels are reached. This occurs because of inactivation of voltage-gated Na+ channels.
Adaptation- Persistent application of suprathreshold stimulus fails to generate repetitive firing.
Refractoriness- A stimulus to the nerve does not elicit a response.
Electrotonus- When a current is passed through electrodes kept on the surface of a nerve, current passes through it resulting in a change in membrane potential and development of electrotonic potential.


Question: Brain blood supply

-        Brain blood supply - 750ml/min OR 55ml/100gm/min OR 13.9% of cardiac output


Question: Melatonin is

(A) Serotonergic # Melatonin is synthesized by pineal parenchymal cells and secreted by them into the blood and CSF.> It is synthesized from serotonin by N-acetylation and O-methylation.> Formation and metabolism of Melatonin: Tryptophan; 5-Hydroxytryptophan 5-Hydroxytryptamine (Serotonin) N-Acetyl -5-methoxytryptamine < (Melatonin) N-Acetyl-Serotonin metabolism 6-Hydroxymelatonin (in Liver) & other metabolites (in brain)


Question: Uni directional flow of a nerve impulse is at

In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another neuron or to the target effector cell. Ref: guyton and hall textbook of medical physiology 12 edition page number: 675,676,677


Question: The commonest cause of primary amenorrhea with ambiguous genitalia in a female with 46XX chromosome

Ans. is 'a' i.e. 21-hydroxylase deficiency Primary amenorrhoea with virilization (ambiguous genitalia) in females is seen in21 hydroxylase def.11 hydroxylase def17-hydroxylase def. does not cause virilization. It causes in females- Primary amenorrhoea and failure of development of secondary sexual characteristics."21-hydroxylase and 11-hydroxylase deficiencies are common; the former accounts for 90-95% of the cases of congenital adrenal hyperplasia, and the latter accounts for all but 1% of the remaining cases."Also know this*Congenital adrenal hyperplasiaIs commonly caused by there 4 enzyme deficiencies.21 hydroxylase def. (Complete)21 hydroxylase def. (Partial)11 hydroxylase def.17 hydroxylase def.21 hydroxylase def. Complete (Salt loosing virilizing)*Hypotension*Virilization (& Precocious puberty in males)*21 hydroxylase def. partial (Simple virilizing)*Normal B.P.*Virilization* (& Precocious puberty in males)*11 hvdroxvlase def.Hypertension*Virilization* (& Precocious puberty in males)*17 hvdroxvlase def. hypertension*Hypertension*No virilization in females*Primary amenorrhoea and failure of development of sec. sec. characteristics in females*Male hermaphrodites*


Question: In human being, the least useful physiological response to low environmental temperature is

Thermoregulation in humans is an impoant aspect of homeostasis. In thermoregulation, body heat is generated mostly in the deep organs, especially the liver, brain, and hea, and in contraction of skeletal muscles. Humans have been able to adapt to a great diversity of climates, including hot humid and hot arid and cold climates. For humans, adaptation to varying climatic conditions includes both physiological mechanisms resulting from evolution and behavioral mechanisms resulting from conscious cultural adaptations.Shivering - Muscles can also receive messages from the thermoregulatory center of the brain (the hypothalamus) to cause shivering. This increases heat production as respiration is an exothermic reaction in muscle cells. Shivering is more effective than exercise at producing heat because the animal (includes humans) remains still. Vasoconstriction - Aerioles carrying blood to superficial capillaries under the surface of the skin can shrink (constrict), thereby rerouting blood away from the skin and towards the warmer core of the body. This prevents blood from losing heat to the surroundings and also prevents the core temperature dropping fuher. This process is called vasoconstriction. Thyroxine - An iodine-containing hormone, produced by the thyroid gland, that increases the rate of cell metabolism.Piloerection - The minute muscles under the surface of the skin called arrector pili muscles (attached to an individual hair follicle) contract (piloerection), lifting the hair follicle upright. This makes the hairs stand on end, which acts as an insulating layer, trapping heat.Ref: Ganong&;s review of medical physiology-24th edition, page no-318


Question: Centriole is absent in

(Liver) (37-Ganong 23rd), Centrioles in hepatocytes cellular and molecular life sciences vol-24, Number 11, 1157-59, DOI 10; 1007/BFO 214785Centrioles which are small cytoplasmic bodies of about 150-200 nm in diameter and 300-350 nm in length concerned with organization in the spindle during cell division have rarely been reported in adult mammalian liver cellsCENTROSOMES - Near the nucleus in the cytoplasm of eukaryotic aniimal cells is a centrosome. The centrosome is made up of two centrioles and surrounding amorphous pericentriolar material* The centrosomes are microtubule - organizing centers (MTOCs) that contain y- tubulin* Centrioles are responsible for the movement of chromosomes during cell divisions (10.K. Sembulingum 5th)* If there is no centriol in the cell, the cell cannot divide. Neurons of postnatal life have no centrioles hence they cannot divide; hence in the post natal life no new neuron formation can occur. But throughout life, death of individuals neurons continue Hence in old age, there is considerable loss of brain mater (8- S.K chaudhari 6th)


Question: Loss of recognition of object by its feel seen with lesion of

(D) Fasciculus cuneatus > Fasciculus cuneatus ends in nucleus cuneatus, conscious proprioception carries out.> Carries crude touch, pressure & position vibration> Fibres from fasciculus cuneatus also end in cerebellum.


Question: Most common site a spontaneous rupture of esophagus is

MC site: left posterolateral side of the distal esophagus


Question: Epinephrine action in liver

Epinephrine markedly stimulates glycogen breakdown in muscle and, to a lesser extent, in the liver. The liver is more responsive to glucagon, a polypeptide hormone that is secreted by the a cells of the pancreas when the blood-sugar level is low Ref: guyton and hall textbook of medical physiology 12 edition page number:419,420,421


Question: Cardiac output increase in exercise by

Ans: a (Increase in HR) Ref: Ganong 22nd ed/ p.632, 633In muscular exercise there is increase in sympathetic activity resulting in increased cardiac contractility and heart rate. Rise in heart rate is the major event that occur in normal individuals compared to increase in contractility, remember Cardiac output = HR X Stroke volumeTherefore, cardiac output increases in normal individuals at the cost of increase in heart rate.


Question: Vitamin B12 intrinsic factor absorption occurs in

Most of the vitamins are absorbed in the upper small intestine, but vitamin B12 is absorbed in the ileum.Vitamin B12 binds to intrinsic factor and the complex is absorbed across the ileal mucosa.Vitamin B12 and folate absorption are Na+ independent.Other vitamins are absorbed by carriers that are Na+ cotranspoers.(Ref: Ganong&;s Review of medical physiology, 23 rd edition, page 458)


Question: Nernst potential of Na+ is

Equilibrium potential of ions is calculated by NERNST EQUATION. For Na, it is +60 mV to +55mV approximately (REF: GANONG'S REVIEW OF MEDICAL PHYSIOLOGY -23rd EDITION. Page No-7)


Question: Lacis cells are located at

The thick end of the ascending limb of the loop of Henle reaches the glomerulus of the nephron from which the tubule arose and nestles between its afferent and efferent aerioles. Specialized cells at the end form the macula densa, which is close to the afferent and paicularly the afferent aeriole .The macula, the neighboring lacis cells, and the renin-secreting juxtaglomerular cells in the afferent aeriole from the juxtaglomerular apparatus.Ref: Ganong&;s review of medical physiology,23rd edition, page: 641


Question: Discharge from Baroreceptors cause inhibition of

Baroreceptor stimulation results in the activation of two mechanisms.
1.    Stimulation of cardiovagal inhibitory centre - Nucleus ambiguous- Leads to Bradycardia.
2.    Inhibition of vasomotor centre - Rostral ventrolateral medulla- Leads to decreased BP.


Question: Siuins are associated with

Siuins are a family of proteins that play a role in aging by regulating cellular health. They're responsible for critical biological functions like DNA expression and aspects of aging. However, siuins can only function in the presence of NAD+, nicotinamide adenine dinucleotide, a coenzyme found in all living cells Ref: guyton and hall textbook of medical physiology 12 edition page number:534,535,536


Question: Coagulation factor VII is

Factor VII (EC 3.4.21.21, blood-coagulation factor VIIa, activated blood coagulation factor VII, formerly known as proconvein) is one of the proteins that cause blood to clot in the coagulation cascade. It is an enzyme of the serine protease class. Ref: guyton and hall textbook of medical physiology 12 edition page number:146,147,148


Question: BRD4 is required for stimulating kinase activity of

Ans: A P-TEFBBromodomain-containing protein 4 is a protein that in humans is encoded by the BRD4 gene.The C-terminal domain of BkD4 has been implicated in promoting gene transcription through interaction with the transcription elongation factor P-TEFb.


Question: 1 cells of duodenum secrete

Enteroendocrine cells (EEC) secrete key gastrointestinal (GI) hormones such as gastric-inhibitory peptide (GIP), cholecystokinin (CCK) and ghrelin that are involved in nutrient sensing pathways and are often implicated in GI pathology. EEC is also known as I cells. Ref: www.pshysoc.org


Question: Increased BP & decreased hea rate is seen in

Cushings reflex is a special type of CNS ischemic response. The cause is raised intracranial tension. When blood flow to the VMC is decreased., it suffers from ischemia. The VMC is stimulated leading to vasoconstriction and increase in BP. There is simultaneous stimulation of cardioinhibitory center by sinoaoic reflex mechanism. ie REFLEX hypeension is associated with bradycardia. Ref: Textbook of medical physiology by N Geetha, 2nd edition, page no. 164


Question: Normal cardiac index is

Experiments have shown that the cardiac output increases approximately in propoion to the surface area of the body. Therefore, cardiac output is frequently stated in terms of the cardiac index, which is the cardiac output per square meter of body surface area. The average human being who weighs 70 kilograms has a body surface area of about 1.7 square meters, which means that the normal average cardiac index for adults is about 3 L/min/m2 of body surface area. Ref: Guyton and Hall textbook of medical physiology 13th edition. Page:245 clinical impoance useful marker of how well the hea is functioning as a pump by directly correlating the volume of blood pumped by hea with body suface area. Normal range is 2.6 to 4.2 L/min/m2 CI less than 2.2L/min/m2 is seen in cardiogenic shock.


Question: At the end of the isometric relaxation phase

At the end of Isovolumetric relaxation, the intraventricular pressures drop to less than the atrial pressure resulting in the opening of Atrioventricular valves Ref : Ganong 25th ed/page 539


Question: Intestinal absorption is faster for

Ans. (a) Hexoses(Ref: Ganong, 25th ed/p.477)Hexose is a monosaccharide with six carbon atomsD-glucose, D-galactose, and D-fructose are hexosesAbsorption is fastest and best for glucose


Question: HC1 secretion in gastric phase is increase by

Acid in the antrum inhibits gastrin secretion, paly by a direct action on G cells and paly by release of somatostatin, a relatively potent inhibitor of gastrin secretion. Th effect of acid is the basis of a negative feedback loop regulating gastrin secretion. Increased secretion of the hormone increases acid secretion, but the acid then feeds back to inhibit fuher gastrin secretion. REFERENNCE ; GANONGS REVIEW OF MEDICAL PHYSIOLOGY 24TH EDITION


Question: Vasopressin is secreted by

Supraoptic nucleus (nucleus supraopticus) one just above the lateral pa of the optic chiasm; many of its cells are neurosecretory in function and project to the neurohypophysis, where they secrete antidiuretic hormone (ADH) and, to a lesser extent, oxytocin; other cells are osmoreceptors that stimulate ADH release in response to increased osmotic pressure.Ref: Ganong&;s review of medical physiology; 24th edition;


Question: Plasma volume is measured by

Plasma volume is measured using dyes like Evans blue that bind specifically to plasma proteins. It will not diffuse into the interstitium. (REF: TEXTBOOK OF MEDICAL PHYSIOLOGY GEETHA N 2 EDITION, PAGE NO - 62)


Question: 'D' cells of stomach secrete

Somatostatin, the growth-hormone-inhibiting hormone originally isolated from the hypothalamus, is secreted as a paracrine by D cells in the pancreatic islets and by similar D cells in the gastrointestinal mucosa. It exists in tissues in two forms, somatostatin 14 and somatostatin 28, and both are secreted. Somatostatin inhibits the secretion of gastrin, VIP, GIP, secretin, and motilin. Its secretion is stimulated by acid in the lumen, and it probably acts in a paracrine fashion to mediate the inhibition of gastrin secretion produced by acidRef: Ganong&;s review of medical physiology 23rd edition Page no: 447


Question: Area number for Somatosensory' area include

1, 2 & 3 (Description: Brodman's areas of Cerebral cortex)


Question: Affiliation refers to

Affiliation orders are legal documents declaring that a man is the father of a child under question.


Question: The given graph likely depicts

The curve is shifted downward and to the right (compliance is decreased) by pulmonary edema and interstitial pulmonary fibrosis. Pulmonary fibrosis is a progressive restrictive airway disease in which there are stiffening and scarring of the lung. The curve is shifted upward and to the left (compliance is increased) in emphysema. Reference: Ganong's Review of Medical Physiology; 25th edition; Page no: 630


Question: Function of hypothalamus is

(B) Involved in thirst and water control > Suprachiasmatic nuclei of hypothalamus and pineal gland have role in controlling circadian rhythm in mammals,> Motor activity is controlled by motor cortex and cerebellum,> Sexual behavior in animal is controlled by Amygdala> Hypothalamus has well documented role in water and thirst control (supra optic nucleus)

Alone or only organ which controls, circadian rhythm

Related with sexual behaviour in animals


Question: Inhibin b hormone has effect on


Question: Fine touch is detected by

Merkel&;s discs are concerned with perception of touch, therefore called tactile receptors. Besides touch sensibility, these receptors also respond to changes in texture, slow vibrations, and sustained pressure. They form the expanded tips and encapsulated endings respectively on the sensory nerve terminals of A fibres. Merkel&;s discs are rapidly adapting receptors. This is why we do not feel our clothes once they are put on.Ref: Textbook of physiology, Dir. Prof. AK Jain, 5th edition


Question: Stimulation of proximal cut end of vagus causes

Stimulation of proximal cut vagus nerve produces apnoea Ref guyton and hall textbook of medical physiology 12 edition page number:370,371,372


Question: Equilibrium potential of calcium is

Applying the Nernst equation to external and internal calcium concentrations of 2.5 mM and 0.0001 mM, respectively, results in an equilibrium potential of +134 mV as shown below. (Ref: www.cvphysiology.com)


Question: Tidal volume is calculated by

Inspiratory capacity minus the inspiratory reserve volume

Total lung capacity minus the reserve volume

Functional residual capacity minus residual volume

Vital capacity minus expiratory reserve volume


Question: Ventero lateral cordotomy for relief of pain in right lower limb due to cutting

Left Lateral spinothalamic tract carries pain fibre from right leg. And ventrolateral cordotomy leads to cut of lateral spinothalamic tract. Ref: Ganong&;s review of medical physiology; 23rd edition; pg:177


Question: Slow wave sleep associated with

Slow wave sleep events (Stage 3 & 4 NREM)
-        Somnambulism
-        Night terrors
-        Nocturnal enuresis
-        Bruxism
-        Sleep talking
-        Delta rhythm- Deep sleep (Stage 3 & 4 NREM)


Question: Proprioception sensation is carried by

Medial lemniscal system or Dorsal column system carries sensation of Fine touch, two-point discrimination, vibrates, Proprioception, Stereognosis.


Question: Transducin is required for

Ans. (d) Vision(Ref: Ganong, 25th ed/p. 178)The G protein coupled receptor in rods is called "Transducin''Role of transducin is to activate the enzyme phosphodiesterase that degrades cGMP


Question: Sensory receptors for pain are


Question: Daily water loss in sweat during high activities

Maximum water loss as sweat is 50 ml /min Sweating is an impoant body temperature regulator mechanism Ref:Guyton and Hall textbook of medical physiology 12th edition,page number:45


Question: Lens derives nutrition from

Lens being an avascular structure receives its nutrition from the aqueous like glucose salts, etc, by diffusion processRef: Parsons diseases of the eye; Under the heading lens


Question: Projections from substantia nigra pars compacta to striatum releases


Question: The normal AV nodal delay is

There is a delay of another 0.09 second in the A-V node itself before the impulse enters the penetrating poion of the A-V bundle, where it passes into the ventricles. A final delay of another 0.04 second occurs mainly in this penetrating A-V bundle, which is composed of multiplemallasciclesassing through the fibrous tissue separating the atria from the ventricles. Thus, the total delay in the A-V nodal and A-V bundle system is about 0.13 second. This delay, in q addition to the initial conduction delay of 0.03 second from the sinus node to the A-V node, makes a total delay of 0.16 second before the excitatory signal finally reaches the contracting muscle of the ventricles.Ref: Guyton and Hall textbook of medical physiology 13th edition. Page:125


Question: Evacuation of the urinary bladder and stool with profuse sweating is a feature of

When even a relatively minor noxious stimulus is applied to the skin it may activate autonomic neurons and produce evacuation of the bladder and rectum, sweating, pallor, and bp swings in addition to withdrawal response. This distressing mass reflex can sometimes be used to give paraplegic patients a degree of bladder and bowel control. Ref: Ganong&;s review of medical physiology;23rd edition; pg:250


Question: Caseous necrosis in granuloma not found in

Caseous necrosis is found in the centre of foci of tuberculous infections.(Ref: Textbook of Pathology HARSH MOHAN 6th Edition page no.45)


Question: Inspiratory depth is halted by

The pneumotaxic center, also known as the pontine respiratory group (PRG), is a network of neurons in the rostral dorsal lateral pons. It consists of the subparabrachial nucleus and the medial parabrachial nucleus. It is considered an antagonist to the apneustic center, which produces abnormal breathing during inhalation. It limits inspiration. Ref: guyton and hall textbook of medical physiology 12 edition page number:370,371,372


Question: In blood, bilirubin is with

Bilirubin formed by the destruction of RBCs is free or unconjugated bilirubin.It is lipid soluble and bound to albumin(protein conjugation),which prevents it's excretion by the kidneys in urine. Ref.Text book of physiology by AK Jain 7th edition page no.79


Question: The rapid depolarization in cardiac muscle is due to

(B) Na++ # Resting membrane potential of individual mammalian cardiac muscle cells is about -90 mV (interior negative to exterior). Stimulation produces a propagated action potential that is responsible for initiating contraction. Depolarization proceeds rapidly, and an overshoot is present, as in skeletal muscle and nerve, but this is followed by a plateau before the membrane potential returns to the baseline. In mammalian hearts, depolarization lasts about 2 ms, but the plateau phase and repolarization last 200 ms or more. Repolarization is therefore not complete until the contraction is half over. With extracellular recording, the electrical events include a spike and a later wave that resemble the QRS complex and T wave of the ECG. As in other excitable tissues, changes in the external K+ concentration affect the resting membrane potential of cardiac muscle, whereas changes in the external Na+ concentration affect the magnitude of the action potential. Initial rapid depolarization and the overshoot (phase 0) are due to opening of voltage-gated Na+ channels similar to that occurring in nerve and skeletal muscle. Initial rapid repolarization (phase 1) is due to closure of Na+ channels. The subsequent prolonged plateau (phase 2) is due to a slower but prolonged opening of voltage-gated Ca2+ channels. Final repolarization (phase 3) to the resting membrane potential (phase 4) is due to closure of the Ca2+ channels and K+ efflux through various types of K+ channels. Voltage-gated Na+ channel in cardiac muscle has two gates--an outer gate that opens at the start of depolarization at a membrane potential of -70 to -80 mV; and an inner gate that then closes and precludes further influx until the action potential ends (Na+ channel inactivation). Slow Ca2+ channel is activated at a membrane potential of-30 to -40 mV. There are three types of K+ channels that proc jce repolarization. The first produces a transient, early outward current (lTO) that produces an early incomplete repolarizai on. Second is inwardly rectifying, ie, at plateau potentials it allows K+ influx but resists K+ efflux, and only at lower membrane potentials does it permit K+ efflux. Current it produces is called lKr. The third type is a slowly activating (delayed rectifying) type that produces a current called IKs. The sum of IKr and IKs is a small net outward current that increases with time and produces repolarization


Question: Mydriasis is due to


Question: Saccharin test is done to assess

(A) Ciliary function # SACCHARIN TEST for nasal mucociliary clearance> A simple test of nasal mucociliary clearance is to place a small particle of saccharin approximately 1 cm behind the anterior end of the inferior turbinate.


Question: UMN includes

Upper motor neuron- Pyramidal cells, corticospinal tract, corticobulbar tract, extrapyramidal tracts.


Question: In infants, defecation often following meal. The cause of colonic contraction in this situation is

Ans. (d) Gastrocolic - reflex(Ref: Ganong, 25th ed/p.504)Distension of the stomach by food - causes contractions of the rectum leading to defecation. This reflex is called gastrocolic reflex


Question: Evacuation of the urinary bladder and stool with profuse sweating is a features of

(Mass reflex) (210-Ganong 22nd) (683-84-Guyt 11th) (250-Ganong 23rd)MASS REFLEX - In chronic spinal animals, afferent stimuli irradiate from one reflex centre to another when even a relatively minor noxious stimulus is applied to the skin, if may irradiate to autonomic centres and produce evacuation of the bladder and rectum, sweating, pallor and blood pressure swings in addition to the withdrawl response* This distressing mass reflex can sometimes be used to give paraplegic patients a degree of bladder and bowel. They can be trained to initiate urination and defecation by stroking or pinching their thighs thus producing an intentional mass reflex.


Question: Ovulation is primarily caused by preovulatory surge of

Estrogen levels peak towards the end of the follicular phase. This causes a surge in levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). This lasts from 24 to 36 hours, and results in the rupture of the ovarian follicles, causing the oocyte to be released from the ovary the oviduct.Ref: Ganong&;s review of medical physiology; 24th edition; page no:-406


Question: During cardiac cycle opening of the aoic valve takes place at

At the end of the Isovolumetric contraction, aoic and pulmonary valves open so that the ventricles can eject blood into the aoa and pulmonary trunk Ref: Ganong 25th ed/page 540


Question: GIT pacemaker is located

Peristalsis is a reflex response that is initiated when the gut wall is stretched by the contents of the lumen, and it occurs in all pas of the gastrointestinal tract from the esophagus to the rectum. The stretch initiates a circular contraction behind the stimulus and an area of relaxation in front of it. When the meal is present, the enteric nervous system promotes a motility pattern that is related to peristalsis but is designed to retard the movement of the intestinal contents along the length of the intestinal tract to provide time for digestion and absorption. Except in the esophagus and the proximal poion of the stomach, the smooth muscle of the gastrointestinal tract has spontaneous rhythmic fluctuations in membrane potential between about -65 and -45 mV. This basic electrical rhythm (BER) is initiated by the interstitial cells of Cajal, stellate mesenchymal pacemaker cells with smooth muscle-like features that send long multiply branched processes into the intestinal smooth muscle. In the stomach and the small intestine, these cells are located in the outer circular muscle layer near the myenteric plexus; in the colon, they are at the submucosal border of the circular muscle layer. In the stomach and small intestine, there is a descending gradient in pacemaker frequency, and as in the hea, the pacemaker with the highest frequency usually dominates.REF: GANONG&;S REVIEW OF MEDICAL PHYSIOLOGY, KIM BARRETT, HEDDWEN BROOKS, SCOTT BOITANO, SUSAN BARMANTWENTY THIRD EDITIONPAGE NO:469,470


Question: The normal intrapleural pressure at the start/beginning of inspiration is ………………………………. cm of H20

The intrapleural pressure becomes more negative at the end of inspiration and less negative at expiration.
It ranges between -3 and -6 mmHg. At the beginning of inspiration, the pressure is -3.8mmHg (-5 cm of water), and at the end of inspiration (beginning of expiration), it is -6mmHg ( -8 cm of water).
The elasticity of lung and rib cage causes it to recoil and thus creating the negative pressure.
The lymphatic drainage of the pleural fluid also creates a negative pressure.


Question: I cells of duodenum secrete

In addition to its secretion by I cells in the upper intestine, CCK is found in nerves in the distal ileum and colon.
It is also found in neurons in the brain, especially the cerebral cortex, and in nerves in many parts of the body.


Question: Pantothenic acid is associated with following moiety

Pantothenic acid is called vitamin B5 It is ised to synthesis co enzyme A in body Ref:Guyton and Hall textbook of medical physiology 12th edition,page number:20,21,22


Question: Heme is conveed to bilirubin mainly in

Heme is conveed to bilirubin by the macrophages of reticuloendothelial system. (Mainly in the spleen, but also in the liver and bone marrow). The tissue macrophage system includes the following phagocytic cells: * In bone marrow - lining of blood sinuses (littoral cells) * In liver - intervals along vascular capillaries (Kupffer cells) * In spleen - in the pulp * In lymph nodes - line the lymphatic paths The destruction of RBCs occur mostly in the capillaries of spleen as they have very thin lumen. Because of this, spleen is called the graveyard of RBCs.


Question: QRS complex indicates


Question: The total volume of CSF is

In humans, the volume of CSF is about 150 mL and the rate of CSF production is about 550 mL/d. Thus the CSF turns over about 3.7 times a day.(Ref: Ganong's Review of Medical Physiology Twenty-Third Edition)


Question: Sarcomere is the area between

The area between two adjacent Z lines is called a sarcomere.(REF TEXTBOOK OF MEDICAL PHYSIOLOGY GEETHA N 2 EDITION, PAGE NO-38)


Question: Seoli cell feedback mechanism involves

Inhibin is one of several proteins that paicipate in differentiation and growth. Two glycoproteins, inhibin A and inhibin B, are secreted by Seoli cells in the testis and granulosa cells in the ovary, inhibiting FSH secretion by direct action on the pituitary.Ref: Ganong&;s review of medical physiology;24th edition; page no:-427


Question: Parvocellular pathway carries signal for detection of

From the Lateral geniculate Nucleus (LGN), a magnocellular pathway (from layers 1 and 2) and a parvocellular pathway (from the rest of the layers) project to the visual coex. Parvocellular Pathway Magnocellular pathway Receive input entirely from type X retinal ganglion cells, trasmit color. Formed by Y ganglion cells, project to magnocellular layers of LGN Convey accurate point-to-point spatial information Color blind, transmitting only black- and white information Terminate in layer 4 C of primary visual coex Terminate in layer 4 C of primary visual coex Moderate velocity of conduction Rapidly conducting pathway Carries signals for color vision, texture, shape , and fine details Carrie signals for detection of movement, depth, and flicker Ref: Guyton and Hall 13th edition Pgno: 663


Question: The period of conditioning of sperms before fertilization is known as

Ans. c (Capacitation). (Ref. Ganong Physiology 22nd ed. 427; Human Embryology by IB Singh)# As fully formed spermatozoa pass through male genital passages they acquire motility (in epididymis) and undergo maturation.# Capacitation is a period of conditioning in the female reproductive tract that lasts for 7 hours. Much of this conditioning, which occurs in the uterine tube, entails epithelial interactions between the sperm and mucosal surface of the tube. During this time a glycoprotein coat and seminal plasma proteins are removed from the plasma membrane that overlies the acrosomal region of the spermatozoa. Only capacitated sperm can pass through the corona cells and undergo the acrosome reaction.# Process by which spermatid becomes spermatozoan is known as spermiogenesis (Spermatogenesis).# Formation of spermatozoa in stages in wall of seminiferous tubules of testis is Spermatogenesis.# The stages are: Spermatogonia (44 XY) >> primary spermatocytes (44 XY) >> secondary spermatocytes (22 X/Y) >> spermatid (22 XY).


Question: Net Filtration pressure in glomeruli of kidney

Net Filtration pressure in glomeruli of kidney- 10-15mmHg


Question: Absorption of glucose in the intestine is by(2018)

The transpo of glucose and galactose depends on Na+ in the intestinal lumen; a high concentration of Na+ on the mucosal surface of the cells facilitates sugar influx into the epithelial cells while a low concentration inhibits sugar influx into the epithelial cells. Because the intracellular Na+ concentration is low in intestinal cells (as it is in other cells), Na+ moves into the cell along its concentration gradient. Glucose moves with the Na+ and is released in the cell (Figure 26-2). The Na+ is transpoed into the lateral intercellular spaces, and the glucose is transpoed by GLUT2 into the interstitium and thence to the capillaries. Thus, glucose transpo is an example of secondary active transpo the energy for glucose transpo is provided indirectly, by the active transpo of Na+ out of the cell. Ref:- Ganong, pg num:- 478


Question: The mechanism that protects normal pancreas from autodigestion is

If the proteolytic enzymes are not released in inactive form, they can cause autodigestion of the pancreas itself.

Proteolytic enzymes secreted in inactive form


Question: Temperature change (Arrows) in Graph of Menstrual cycle is due to

Progesterone (Description: Temperature increase of 0.5 degrees Post Ovulation is due to Progesterone)


Question: Maximum absorption of water takes place in

Ascending limb of the loop of Henle and an early segment of distal tubule is impermeable to water. Maximum of filtered water (60-70%) is reabsorbed in the proximal tubule, with or without Vasopressin. This is independent of the fluid and electrolyte status of the body.


Question: Action of calmodulin isa) Ca2+ dependentb) Through calmodulin dependent kinasesc) Through cAMP dependent kinasesd) Through cGMP dependent kinases

Calcium and calmodulin forms a complex which activates myosin kinase that phosphorylates myosin head. Myosin kinase is a muscle phosphorylase.


Question: Sperm acquires motility in

The seminiferous tubules of the testes are the staing point for the process, where spermatogonial stem cells adjacent to the inner tubule wall divide in a centripetal direction--beginning at the walls and proceeding into the innermost pa, or lumen--to produce immature sperm. Maturation occurs in the epididymis Ref: guyton and hall textbook of medical physiology 12 edition page number:625,626,627


Question: Purkinje cells are inhibitory for

Deep cerebellar nuclei are initially excited by sensory afferents but a fraction of a second later they are inhibited by Purkinje cell output Ref: Ganong 25th ed/page 250


Question: Hemoglobin first appears in

Hb synthesis sta in the stage of intermediate normoblast and then its content increase rapidlyRef: Medical Physiology Indu Khurana 2015 edition page No:106


Question: First change of improvement, noted after iron therapy is initiated

12-24 hr Replacement of intracellular iron enzymes; subjective improvement; decreased irritability; increased Appetite 36-48 hr Initial bone marrow response; erythroid hyperplasia 48-72 hr Reticulocytosis, peaking at 5-7 days 4-30 days Increase in hemoglobin level 1-3 mo Repletion of stores


Question: Predominant ion in saliva is

During saliva production, K+ and Hco3- are secreated of which Hco3- >>  K+ secreted.


Question: Central chemoreceptors are most sensitive to following changes in blood

A rise in aerial PCO2 stimulates the RVLM Neurons located near the pial surface of the medulla in the rostral ventrolateral medulla (RVLM) are the central chemoreceptors Carbon dioxide can cross the blood-brain barrier easily and rapidly and causes changes Ref: Ganong's Review of Medical Physiology Twenty-Third Edition Page No: 562 CO2diffuses readily into CSFand is immediately hydrated to form H2CO3.H2CO3 dissociates to form H+ and HCO3-. So blood pCO2 influences the pH of CSF


Question: S.A. node acts as a pacemaker of the hea because of the fact that it

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

Is capable of generating impulses spontaneously


Question: Enterohepatic circulation is necessary for the secretion of

Bile is made up of the bile acids, bile pigments, and other substances dissolved in an alkaline electrolyte solution that resembles pancreatic juice. About 500 mL is secreted per day. Some of the components of the bile are reabsorbed in the intestine and then excreted again by the liver (enterohepatic circulation). In addition to its role in digestion and absorption of fats (Chapter 27), bile (and subsequently the feces) is the major excretory route for lipid-soluble waste products.Ref: Ganong&;s review of medical physiology 23rd edition Page no: 482


Question: In anemia the concentration of 2,3 DPG is


Question: In humans, effective renal blood flow is

625Measure of Effective Renal Plasma Flow (ERPF):Is through PAH clearance In normal adult is about 625 ml/minuteHowever, PAH underestimates the effective renal plasma flow by about 10%.Therefore, actual renal plasma flow is about 700 ml/min.


Question: Broca's area is concerned with

Broca's area or areas 44, 45 is a region in the frontal lobe with functions linked to speech production. Broca's area also plays a significant role in language comprehension. Lesions involving the Broca's motor speech area results in motor aphasia, also known as Broca's aphasia. Ref: guyton and hall textbook of medical physiology 12 edition page number: 841,842,843


Question: Masculine or feminine features most directly depend on

Ans. d (Serum testosterone levels). (Ref. Ganong, Physiology, 21st ed., 420)TestosteroneSource Testis (Leydig cells), adrenalPotency DHT> testosterone > androstenedioneTargets Skin, prostate, seminal vesicles, epididymis, liver (MH-2000)Functions1.Differentiation of wolffian duct system into internal gonadal structures. 2.Secondary sexual characteristics and growth spurt during puberty. 3.Required normal spermatogenesis. 4.Anabolic effects on muscle size, RBC production 5.Increases libido# Testosterone is converted to DHT by the enzyme 5 a-reductase, which is inhibited by finasteride. FunctionsAndrogen binding protein (ABP)Ensures that testosterone in seminifierous tubule is high.Inhibininhibits FSHTestosteroneDifferentiates male genitalia, has anabolic effects on protein metabolism, maintains gametogenesis, maintains libido, inhibits GnRH, and fuses epiphyseal plates in bone.FSHSertoli cells >> function >> sperm production (spermiogenesis)LHLeydig cell


Question: Intubation induced laryngeal spasm can not be prevented by

Promethazine can increase the chances of reflex disturbances.


Question: Nerve depolarization is due to

When sodium ion enters a cell the potential goes positive side and this is depolarization phase. (REF: TEXTBOOK OF MEDICAL PHYSIOLOGY GEETHA N 2 EDITION, PAGE NO - 26)


Question: Nerve fibers involved in proprioception

Ans. (a) Type A fiber(Ref: Ganong, 25th ed/p.94)Erlanger and Gasser classified nerve fibers in to three types A, B and C based on their diameter, degree of myelination and conduction velocities.The classification is for both sensory and motor nerve fibers. The classification is as follows,Fiber TypeMyelin Present or AbsentDiameter(um)Conduction Velocity (m/s)FunctionsA aMyelinated12-20 (Largest)70-120 (Highest)Proprioception; somatic motorA bMyelinated5-1230-70Touch, pressureA gMyelinated3-615-30Motor to muscle spindlesA dMyelinated2-512-30Pain, temperatureBMyelinated<33-15Preganglionic autonomicC, dorsal rootUnmyelinated0.4-1.2 (Smallest)0.5-2 (lowest)Pain, temperatureC, SympatheticUnmyelinated0.3-1.30.7-2.3Postganglionic sympathetic


Question: Slow waves are maximum in

Among the given options, slow waves are maximum in the ileum. The rate of slow waves in ileum is 8/min. Slow waves or Basic Electric rhythm(BER) refers to the spontaneous rhythmic fluctuation in membrane potential of the GI smooth muscles (betwee -65mV and -45mV). These are initiated by the interstitial cells of Cajal. Other options The rate of slow waves in the stomach is 4/min and in the colon, it varies between 2 to 6/min. Rate of Basal electric rrhythm in various regions Segment Rate of BER Stomach 4/min Duodenum 12/min Distal ileum 8/min Cecum 2/min Sigmoid 6/min Ref: Ganong&;s Review of Medical physiology 26th edition Pgno: 486


Question: Slow waves/ BER are in increasing order in the following pas of GIT

"Waves occur 3-4 times per minute in the stomach. In the small intestine, there is an average of 12 BER cycles/min in the proximal jejunum, declining to 8/min in the distal ileum. The frequency of the wave increases along the colon, from about 2/min at the ileocecal valve to 6/min at the sigmoid."


Question: The principle that is the spinal cord dorsal roots are sensory and the ventral roots are motor is known as

In the spinal cord fact that the dorsal roots are sensory and the ventral roots are motor is called Bell-Magendie law. The anterior spinal nerve roots contain only motor fibers and posterior roots only sensory fibers and that nerve impulses are conducted in only one direction in each case. Ref: guyton and hall textbook of medical physiology 12 edition page number:672,673,674


Question: Earliest change in iron deficiency anaemia is

Ferritin is a blood cell protein that contains iron. A ferritin test helps your doctor understand how much iron your body is storing. If a ferritin test reveals that your blood ferritin level is lower than normal, it indicates your body's iron stores are low and you have iron deficiency Ref:guyton and hall textbook of medical physiology 12 edition page number:118,119,120


Question: Glucose sympo occurs with

Glucose transpo in the intestine is associated with sodium transpo Ref: guyton and hall textbook of medical physiology 12 edition page number:429,430,431


Question: In blood bilirubin is with

Bilirubin is bound to protein for transportation in blood.


Question: Nucleus gracilis and Nucleus cuneatus are the first synapses for

(A) Dorsal columns > Primary afferent neurons are located in dorsal root ganglion cells, and fibers (group II) ascend ipsilaterally and coalesce in the fasciculus gracilis or fasciculus cuneatus.> And these two fasciculi form the dorsal columns of the spinal cord and ascend the length of the spinal cord to nucleus gracilis and nucleus cuneatus of the medulla.> The Fasciculus gracilis consists of fibres from sacral and lumbar region and Fasciculus cuneatus receives its fibres from thoracic and cervical.


Question: Iron is actively absorbed in

Active absorption of iron occurs in duodenum & proximal jejunum. In stomach absorption of alcohol (20%) & drugs like aspirin takes place. In large intestine, absorption of acids and bases, water, remainder of sodium (Na) and potassium (K) i.e. remaining because not already absorbed in the small intestine takes place. The function of ileum is mainly to absorb VitaminB12 & bile salts. Ref: Guyton,11e


Question: While walking or standing posture is maintained by

The cerebellum receives information from the sensory systems, the spinal cord, and other pas of the brain and then regulates motor movements. The cerebellum coordinates voluntary movements such as posture, balance, coordination, and speech, resulting in smooth and balanced muscular activity. Ref: guyton and hall textbook of medical physiology 12 edition page number:780,781,782


Question: The node of Ranvier is seen in

Nodes of Ranvier are periodic gaps in the myelin sheath on the axon.
A neuron is a functional unit (the basic unit of nervous tissue).
It is specialized for the function of reception, integration and transmission of information in the body,
The basic structure of the neuron is best studied in a spinal motor neuron,
This cell has a ‘cell body (soma)' with 5-7 small processes called ‘dendrites'.
There is a long process called ‘axon’ that originate from “axon hillock (A thickened area of cell body from which axon originates)”.
The first portion of the axon is called “initial segment”.
In a motor neuron, the axon hillock and the initial segment of axon have the lowest threshold for excitation


Question: A person's electrocardiogram (ECG) has no P wave, but has a normal QRS complex and a normal T wave. Therefore, his pacemaker is located in the

The absent P wave indicates that the atrium is not depolarizing. Therefore, the pacemaker cannot be in the sinoatrial (SA) node. Because the QRS and T waves are normal, depolarization and repolarization of the ventricle must be proceeding in the normal sequence. This situation can occur if the pacemaker is located in the atrioventricular (AV) node. If the pacemaker were located in the bundle of His or in the Purkinje system, the ventricles would activate in an abnormal sequence (depending on the exact location of the pacemaker) and the QRS wave would have an abnormal configuration. Ventricular muscle does not have pacemaker propeies.


Question: Pubarche is due to

Pubarche refers to the first appearance of pubic hair at pubey. Pubarche is one of the physical changes of pubey and can occur independently of complete pubey Ref: guyton and hall textbook of medical physiology 12 edition page number:636,637,638


Question: The conversion of short term memory to long term memory is done in

The conversion of short term memory to long term memory is done in hippocampus.


Question: The inhibitory neurotransmitter in CNS neurons is

GABA and Glycine are the chief inhibitory neurotransmitters in CNS.


Question: Most important stimulant for bile secretion is

Bile salts are the most important cholerectic or the substance that increases bile secretion. Cholecystokinin (CCK) is the most important cholagogue or substance that increases gallbladder contraction.


Question: Largest amounts of prostaglandins are seen in

Largest amounts of prostaglandins are seen in seminal fluidEach seminal vesicle is a touous, loculated tube lined with a secretory epithelium that secretes a mucoid material containing an abundance of fructose, citric acid, and other nutrient substances, as well as large quantities of prostaglandins and fibrinogen.Prostaglandins are believed to aid feilization in two ways: (1) by reacting with the female cervical mucus to make it more receptive to sperm movement and (2) by possibly causing backwards, reverse peristaltic contractions in the uterus and fallopian tubes to move the ejaculated sperm toward the ovariesGuyton 13e pg: 1020


Question: Mean circulatory filling pressure is

When hea pumping is stopped by shocking the hea with electricity to cause ventricular fibrillation or is stopped in any other way, flow of blood anywhere in circulation ceases a few seconds later. Without blood flow the pressure everywhere in circulation become equal. This equilibrated pressure level is called mean circulatory filling pressureRef: Guyton and Hall, Textbook of medical physiology, 2ndSouth Asia Edition

Difference between systemic and pulmonary aerial pressure

Difference between central venous pressure and central aerial pressure

Aerial pressure taken at the point when hea stops beating


Question: During diastole, arterial pressure is maintained by


Question: If one of your nerves is compressed and this leads to paresthesia for sometime, the type of nerve fibre affected most probably is


Question: Direction of sound is differentiated by

Ans. (d) Inferior colliculus(Ref: Kandel, Principle of Neural Sciences, 5th ed, p.697)All auditory pathways ascending through the brain stem converge in inferior colliculusHelps in localization of sound and the direction from which the sound comes


Question: Sucrose space is about

The sucrose gap technique is used to create a conduction block in nerve or muscle fibers. A high concentration of sucrose is applied to the extracellular space, which prevents the correct opening and closing of sodium and potassium channels, increasing resistance between two groups of cells. It was originally developed by Robe Stampfli for recording action potentials in nerve fibers, and is paicularly useful for measuring irreversible or highly variable pharmacological modifications of channel propeies since untreated regions of membrane can be pulled into the node between the sucrose regions Ref: guyton and hall textbook of medical physiology 12 edition page number:475,476,477


Question: The difference between skeletal and smooth muscle contraction and relaxation is/area) Troponin (+ve)b) Myosin light chain kinasec) Ca2+d) Actine) Myosin

Troponin is absent in case of smooth muscles but present in skeletal muscles.

Myosin light chain kinase is involved in case of smooth muscle contraction, but not in skeletal muscles.


Question: Total body water is

In the average young adult male, 18% of the body weight is protein and related substances, 7% is mineral, and 15% is fat. The remaining 60% is water.(REF: GANONG'S REVIEW OF MEDICAL PHYSIOLOGY 23rd EDITION page no.2)


Question: A person with eyes closed & mind wondering will have the following wave in

(A) a-waves # Alpha Rhythm> In adult humans who are awake but at rest with the mind wandering and the eyes closed, the most prominent component of Ihe EEG is fairly regular pattern of waves at a frequency of 8-12 Hz and an amplitude of 50-100 pV when recorded from the scalp> This pattern is the alpha rhythm.> It is most marked in the parieto-occipital area.


Question: During regulatory volume decrease, many cells will increase

K+ is the major intracellular ion; efflux of K+ will produce an osmotic flow of water out of the cell. Water exit will lead to a decrease in cell volume.An influx of Na+ and synthesis of sorbitol do not occur during this process because both processes would increase intracellular osmolytes and drive water into the cell, increasing cell volume.Ref: Guyton; 13th edition


Question: Kupffer cells are a type of

Macrophages (Kupffer Cells) in the Liver Sinusoids.ln the liver sinusoids, lined with tissue macrophages called Kupffer cellsRef: Guyton and Hall textbook of medical physiology 13th edition. Page: 459


Question: After a meal rich in carbohydrate, insulin secretion is stimulated by


Question: Entropion is

Entropion is a condition in which the lower eyelid turns inward, rubbing against the eye. Entropion occurs most commonly as a result of aging. Infection and scarring inside the eyelid are other causes of entropion.


Question: CSF pressure is mainly regulated by

Lumbar CSF pressure is normally 70 to 180 mm H2O. Up to pressures well above this range, the rate of CSF formation is independent of intraventricular pressure. However, absorption is propoional to the pressure Ref: Ganong's Review of Medical Physiology Twenty-Third Edition Page No:571


Question: Nissl's bodies located intracytoplasmic are in

Nissl bodiesLarge granular bodies that stain with basic dyes, forming the reticular substance of the cytoplasm of neurons, composed of rough endoplasmic reticulum and free polyribosomes.Ref: Ganong&;s review of medical physiology; 24th edition


Question: Most important function of albumin in body is

Osmotic pressure is determined by the number of molecules dissolved in a fluid rather than by the mass of these molecules. Therefore, when corrected for number of molecules rather than mass, the following chart gives both the relative mass concentrations (g/dl) of the different types of proteins in normal plasma and their respective contributions to the total plasma colloid osmotic pressure (Πp).


Question: Mechanism of analgesia is bya) Nociceptin stimulationb) Nocistatin stimulationc) Anandamide receptorsd) Nicotinic & cholinergic receptors

Nocistatin stimuli inhibit nociceptors and produce analgesia.
Anandamide (a cannabinoid) produces analgesic effect by binding to CB1 receptors.
Acetylcholine and nicotinic cholinergic receptors (subunits α4 and β 2) are involved in regulation of pain.


Question: Nitric oxide is produced in

Nitric oxide is formed from Arginine, released from endothelial cells and acts through cGMP to cause vasodilation.
It is also believed to be involved in gastrointestinal smooth muscle relaxation by acting as a neurotransmitter.


Question: The most important buffer in RBC is


Question: Sequence of vesicle transpo is

B i.e. ER-+Cis-+Trans--+Cell membrane Golgi apparatus serves as a unique soing & packing deviceQ, that receives newly synthesized proteins, all containing signal or transit peptide from endoplasmic retinaculum. It rejects proteins with no signal or transit peptide without processing and that remain as cytoplasmic protein. Golgi complex (apparatus) / Dictyosome It is a collection of smooth membrane enclosed sacs (cisterns) that are stalked like dinner plates, usually near the nucleus. It has membrane similar to those of smooth ER. It is usually composed of ..4 stalked layers of 6 sacs in each apparatus It is a polarized structure with a cis (proximal) and trans (distal) sidesQ


Question: Circulatory shock is an example of


Question: Sperms acquire motility in

Sperm motility describes the ability of sperm to move properly through the female reproductive tract. the ability to move forward is acquired in the epididymis Ref: Ganong&;s review of medical physiology; 24th edition; page no:-422


Question: Shivering is controlled by

Temperature Regulation Center: hypothalamic temperature regulation center acts as both a very sensitive sensory center (sensing brain temperature) and as an integration center, to maintain core temperature. Action: Compares input information on brain temperature (very sensitive) and skin temperature (less sensitive) with some "Reference" value or temperature ("Set Point"), and adjusts effectors to maintain actual temperature at the reference value (negative feedback loop). Fever: 1. Mechanism: Most common fevers are due to an increase in temperature regulation set point, due to agents called "pyrogens" pyrogen => hypothalamic set point increase 2. Pyrogenic Agents bacterial endotoxin bacterial debris antigen-antibody complexes neoplastic disease mechanical tissue trauma etc. 3. Body Temperature Changes a. Onset: actions to raise body temperature b. Termination: actions to lower temperature Ref: guyton and hall textbook of medical physiology 12 edition page number 856,857,858


Question: The site of action of vasopressin is

Vasopressin (ADH) Increasing the water permeability of distal tubule and collecting duct cells in the kidney, thus allowing water reabsorption and excretion of more concentrated urine. Ref: Ganong's Review of Medical Physiology; 24th edition; page no: 698


Question: In muscle cells, resting membrane potential is equal to the isoelectric potential of

The isoelectric potential of Cl- is -70mV and of K+ is -90mV.
According to ‘Ganong’ and ‘Principles of Medical Physiology’, the actual measured RMP of a nerve fibre is -70mV rather than the calculated value of -90mV.
So in nerve fibres, the RMP is equal to or closer to the isoelectric potential of Cl-.
Whereas in muscle cells, the RMP is -90mV, which is equal to the isoelectric potential of K+.


Question: Least reabsorption out of

Reabsorption the flow of glomerular filtrate from the proximal tubule of the nephron into the peritubular capillaries, which allows the selective passage of ceain substances (glucose, proteins, sodium) back into the circulation. Urea is least reabsorbed as it is excreted out. Ref: Ganong's review of medical physiology; 24th edition


Question: Generator area in a nerve cell is

The first poion of the axon is called the initial segment. The Initial segment in spinal motor neurons, the initial node of Ranvier in cutaneous sensory neurons is a site where propagated action potentials are generated.(Ref: Ganong's Review of Medical Physiology Twenty-Third Edition)


Question: Insulin mediated glucose uptake occurs through


Question: Decreased ability to smell is

(B) Hyposmia # Hyposmia: Hyposmia is a state of decreased sensation of smell> Disorders of the Sense of Smell: Transport losses - Rhinitis, polyps/neoplasms of nasal cavity Sensory losses - Drugs, radiation therapy, toxin exposure Neural losses - Alps, alcoholism, Alzheimer's, Kallman syndrome, hypothyroidism etc.,> Treatment: There is no proven treatment for sensorineural olfactory losses. Fortunately, spontaneous recovery often occurs.> Zinc and vitamin therapy (especially with vitamin A) are advocated by some.> Profound zinc deficiency can produce loss and distortion of the sense of smell but is not a clinically important problem except in very limited geographic areas


Question: Coronary blood flow regulated by

Ans. is 'c' i.e., Local muscle action and reflexesRegulation of coronary blood flow mainly occurs by chemical regulation through autoregulation.Regulation of coronary blood flowRegulation of coronary flow occurs by two mechanisms : ?1) Chemical regulation (Autoregulation)Regulation of coronary blood flow occurs through local intrinsic regulation, i.e., autoregulation, most likely through the production of vasodilating metabolites in response to minimal degree of ischemia. The vasodilatory chemical stimuli are low PO2, High PCO2, H+, K+, lactic acid, ADP AMP and adenosine. Chemical regulation (autoregulation) of coronary blood flow is far more impoant than neural regulation.2) Neural regulationCoronary aeries are supplied by autonomic sympathetic and parasympathetic system. Coronary aeries have both alpha and beta sympathetic (adrenergic receptors), with the beta receptors predominating. Beta receptor stimulation produces vasodilation whereas alpha receptor stimulation produces vasoconstriction. There are relatively few parasympathetic (vagal) fibers supplying the coronary aeries. The direct effect of these fibers is vasodilatation; But indirect effect causes vasoconstriction and predominates. Indirect effect is the result of decrease in formation of vasodilator metabolites due to decrease in hea rate and cardiac contractility.


Question: If a single spinal nerve is cut, the area of tactile loss is always greater than the area of loss of painful sensations, because

Receptor field overlapping is lowest for temperature. Tactile receptor fields overlap higher than temperature. Highest overlapping is for pain. Temperature < Touch < Pain.
So the inverse will be true for loss of sensation. Loss of sensation highest in Temperature since it has no overlapping.  And the loss of sensation will be lowest for pain.

Tactile information is carried by myelinated fast conducting fibres

Degree of overlap of fibres carrying tactile sensation is much less

In the primary sensory cortex tactile sensation is represented on a larger area


Question: Intrinsic factor is secreted by

The substance intrinsic factor, essential for absorption of vitamin B12 in the ileum, is secreted by the parietal cells along with the secretion of hydrochloric acid. -G cells of antrum of stomach secrete hormone gastrin whose primary actions include stimulation of gastric acid secretion & stimulation of growth of gastric mucosa. -Pepsinogen secreting cells(peptic cells of oxyntic glands) secrete pepsinogen(proenzyme) which is conveed to pepsin (active form) by action of HCl.Pepsin is a proteolytic enzyme that regulates protein digestion. -The pyloric glands secrete mainly mucus for protection of the pyloric mucosa from the stomach acid. They also secrete the hormone gastrin. Reference: Guyton,11e


Question: Sleep center is located in

Ans. (c) Hypothalamus(Ref: Ganong, 25th ed/p.273)Preoptic nucleus of hypothalamus particularly ventrolateral preoptic nucleus promotes sleep


Question: Role of bile salts

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 intestinalepithelial cells, where they are absorbedREF: GANONG&;S REVIEW OF MEDICAL PHYSIOLOGY, KIM BARRETT, HEDDWEN BROOKS, SCOTT BOITANO, SUSAN BARMANTWENTY THIRD EDITIONPAGE NO:439,440


Question: K+ homeostasis in human is

Electrolytes are substances that dissociate in solution and have the ability to conduct an electrical current. These substances are located in the extracellular and intracellular fluid. Within the extracellular fluid, the major cation is sodium and the major anion is chloride. The major cation in the intracellular fluid is potassium. These electrolytes play an impoant role in maintaining homeostasis. In this aicle, the etiology, signs, symptoms, and treatments for imbalances of these three electrolytes are reviewed. Ref guyton and hall textbook of medical physiology 12/e pg58

An essential electrolyte for different organ function


Question: Acidophils of the anterior pituitary secrete

Acidophils of the anterior pituitary (adenohypophysis) secrete growth hormone and prolactin. Basophils secrete TSH, ACTH, FSH and LH. Cells of Anterior pituitary Ref: Guyton and Hall 13th edition Pgno: 940


Question: The primary motor area for shivering is

Functions of Hypothalamus
-        Thermoregulation- Preoptic region

Anterior hypothalamus- Heat response
Posterior hypothalamus- Cold response

-        Satiety centre- ventromedial nucleus
-        Feeding centre- Lateral nucleus
-        Circadian rhythm- Suprachiasmatic nucleus
-        Sleep
-        Sex drive-  Anterior hypothalamus, Posterior hypothalamus.
-        Hypophysis regulation


Question: A lesion of the ventrolateral part of the spinal cord will lead to the loss (below the level of the lesion) of

Sensations carried by the posterior column
-        Proprioception, Vibration, kinesthesia, fine touch.
Sensations carried by the anterolateral column
-        Temperature, pain (lateral) and crude touch (anterior)
Crossing over of fibers occurs in case of the anterolateral system.

Proprioception on the contralateral side

Pain sensation on the contralateral side


Question: Skeletal framework of a cell is maintained by

It is a pa of cytoskeleton Microtubules are major components of the cytoskeleton. They are found in all eukaryotic cells, and they are involved in mitosis, cell motility, intracellular transpo, and maintenance of cell shape. Microtubules are composed of alpha- and beta-tubulin subunits assembled into linear protofilaments. Ref guyton and hall textbook of medical physiology 12/e p22


Question: Vomiting centre is situated in the

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: Ductal development of breast is caused by

Estrogen, or oestrogen, is the primary female sex hormone. It is responsible for the development and regulation of the female reproductive system and secondary sex characteristics. There are three major endogenous estrogens in females that have estrogenic hormonal activity: estrone, estradiol, and estriol Ref: guyton and hall textbook of medical physiology 12 edition page number: 636,637,638


Question: 'Malignant pustule' is

A congested edematous ulcer area with central necrosis and surrounding black ischar and satellite lesions is called "malignant pustule".


Question: Myelin contains protein to lipid ratio as


Question: Secretion of estrogen is maximum at

Estrogen is a generic term for any of the estrus-producing compounds (female sex hormones), including estradiol, estriol, and estrone. Called also estrogenic hormone. In humans, the estrogens are formed in the ovary, adrenal coex, testis, and fetoplacental unit, and are responsible for female secondary sex characteristic development, and during the menstrual cycle, act on the female genitalia to produce an environment suitable for feilization, implantation, and nutrition of the early embryo.Ref: Ganong&;s review of medical physiology; 24th edition; page no: 405


Question: Left ventricular systole corresponds

Left ventricular systole corresponds to atrial diastole Ref: guyton and hall textbook of medical physiology 12 edition page number:199,200,201


Question: Venodilation in most of the tissue due to

(Decreases O2 tension): Ref: Mechanisms of clinical signs - Google Books Result books.google.co.in/books?isbn=072958075xMark Dennis, William Talbot Bowen, Lucy Cho - 2012 - MedicalLivedo Reticularis is essentially increased visibility of the venous plexus of the skin. Venodilatation of the vessels and deoxygenation of blood in the plexus are two main factors. In general venodilatation is caued by altered autonomic nervous system function; circulating factors that cause Venodilation; or in response to local hypoxia. Venodilation allows more venous blood to be present in engorged venules, making them larger and easier to see through the skin. Deoxygenation is principally caused by decreased cutaneous perfusion which can be as a result of decreased arteriolar inflow (may be due to vasopasm due to cold, ANS activity, arteriolar thrombosis or increased blood viscosity); or decreased venous outflow (may be due to venous thrombosis, increased blood viscosity)


Question: Least absorption out of the following through the kidney is for

Urea is minimally absorbed. Ref: guyton and hall textbook of medical physiology 12 edition page number:491,492,493


Question: The ECG change seen in hyperkalemia is

Hyperkalemia (plasma K+ +-7.0 meq/L). The PR and QRS intervals are within normal limits. Very tall, slender peaked T waves are now present. Hyperkalemia (plasma K+ +-8.5 meq/L). The QRS complex is broad and slurred and the QRS interval has widened to 0.2 s. The T waves remain tall and slender Fuher elevation of the plasma K+ level may result in ventricular tachycardia and ventricular fibrillation. Ref: Ganong's Review of Medical Physiology Twenty-Third Edition Page No: 504


Question: Best absorbable monosaccharide

End products of carbohydrate digestion are monosaccharides,most impoant of which is GLUCOSE . maximum rate of glucose absorption from intestine is about 120 gm/hour Ref.Textbook of physiology by AK Jain 7th edition page no.264


Question: Increased oxygen delivery to tissues in response to increased CO2 is

The Bohr effect is a physiological phenomenon first described in 1904 by the Danish physiologist Christian Bohr: hemoglobin's oxygen binding affinity is inversely related both to acidity and to the concentration of carbon dioxide Ref: guyton and hall textbook of medical physiology 12 edition page number:353,354,355


Question: Parasympathetic stimulation of the hea accompanied by a withdrawal of sympathetic tone to most of the blood vessels of the body is characteristic of

The fight-or-flight response and exercise are characterized by the increased sympathetic tone and decreased parasympathetic tone.The diving response is associated with increased parasympathetic and sympathetic tone.The cold pressor response is characterized by increased sympathetic activity to the hea and blood vessels.Emotional Fainting--Vasovagal Syncope: An interesting vasodilatory reaction occurs in people who experience intense emotional disturbances that cause fainting. In this case, the muscle vasodilator system becomes activated and, at the same time, the vagal cardioinhibitory center transmits strong signals to the hea to slow the hea rate markedly. The aerial pressure falls rapidly, which reduces blood flow to the brain and causes the person to lose consciousness. This overall effect is called vasovagal syncope. Emotional fainting begins with disturbing thoughts in the cerebral coex.Ref: Guyton; 13th edition; Chapter 18 Nervous Regulation of the Circulation and Rapid Control of Aerial Pressure


Question: Intracellular receptors are found in

Receptors for steroid and thyroid hormones are located inside target cells , in the cytoplasm or nucleus , function as ligand dependent transcription factors ....Being lipids, steroid hormones enter the cell by simple diffusion across plasma membrane whereas thyroid hormones enter by facilitated diffusion. Ref guyton and hall textbook of medical physiology 12/e p887-888


Question: The depth of respiration is controlled by

Pneumotaxic center limits inspiration by inhibiting Apneustic center Ref: Ganong 25th ed/page 65


Question: Urine concentrating ability of the kidney is increased by

Countercurrent mechanism is a system in the renal medulla that facilitates concentration of the urine as it passes through the renal tubules.Ref: Ganong&;s review of medical physiology; 24th edition; page no: 687


Question: Seoli cell secrets

Androgen binding protein is a protein secreted by testicular Seoli cells along with inhibin and mullerian inhibiting substance. Androgen binding protein probably maintains a high concentration of androgen in the seminiferous tubules.Ref: Ganong&;s review of medical physiology; 24th edition; page no: 421


Question: An action potential is initiated at the Axon Hillock or Initial segment of the neuron because

Neurotransmitter is released at this site

Has lowest concentration of voltage gated sodium channels