PSL201 Final Exam 2007

PSL201 Final Exam 2007 - Name Student Number Questions...

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Unformatted text preview: Name Student Number Questions needing attention (:1 . W' DEPARTMENT OF PHYSIOLOGY UNIVERSITY OF TORONTO APRIL/MAY EXAMINATIONS 2007 PSL201Y1 Duration — 3 hours 89 Questions (23 pages) Examination Aids: NO AIDS ALLOWED INSTRUCTIONS 1. Bubble in your family name beginning in column 1 of the NAME field. 2. Bubble in your student number, beginning in column 1 of the Student Number field. 3. There are several versions of this question paper. Each contains the same questions, but their sequence varies. Question 1 identifies the Version that you have been given. THE CODING OF THIS QUESTION ON YOUR COMPUTER CARD MUST BE DONE CORRECTLY AND APPEALS THAT A STUDENT MADE AN ERROR WILL NOT BE ACCEPTED. 4. Questions 2—38 each have weight of 1. All other questions have a weight of 0.5 5. Spelling and/or typing errors do not make a statement incorrect. 6. Invigilators are not permitted to interpret questions to individual students. If you think a question is ambiguous, answer as you understand it, then explain your reasoning on your question book, not on the Answer Card. You must also record the question number on the line, "Questions needing attention" at the top of this page. 7. Both your computer card and your signed question paper must be handed in at the end of the examination. 1. Fill in “A” as a coding question Material covered in Term Tests - 1 mark/question Introduction - Wojtowicz 2. Which of the following best illustrates the concept of negative feedback? A. Contractions of the uterus push the fetus against cervix, which triggers release of oxytocin into the bloodstream; oxytocin then stimulates stronger contractions of the uterus. B. Increase in body temperature stimulates sweat glands excretion, which produces heat loss; heat loss lowers body temperature and reduces activity in the brain thermoregulatory center. C. During action potential sodium ions flow into the cell, this produces cell depolarization which open voltage-dependent ion channels; voltage-dependent ion channels further depolarize the cell. D. During heat exhaustion the excessive sweating produces loss of blood volume, which in turn produces a reduction in blood pressure; this is experienced as dizziness after heavy exercise. 3. The Nemst Equation describes the equilibrium conditions for particles passing across biological membranes. Which force and/or factor DOES NOT play a part in this equilibrium. A. polarity of charged particles B. permeability of membrane to particles C. concentration of particles D. osmotic pressure inside the cell 4. Crossbn'dge cycle describes interactions between: A. molecules of neurotransmitter passing across the synaptic cleft B. ionic channels in the muscle membrane C. muscle membrane and contractile proteins D. actin and myosin 5. Autonomic nervous system innervates: A. the post-ganglionic chain belonging to the parasympathetic division of the nervous system all muscle fibers except the smooth muscle and cardiac muscle practically all organs including the blood vessels effector organs such as the heart muscle, smooth muscle in the eye, respiratory muscle and sweat glands F70!” According to the concept of dual innervation by the autonomic nervous system, if sympathetic activity inhibits pancreatic secretions, then the parasympathetic nervous system should A. B. C. D. inhibit pancreatic secretions as well stimulate pancreatic secretions have no effect on pancreatic secretions stimulate blood flow to the intestine to enhance food absorption Respiration — Goode 7. 9) 10. Which of the following is the best measurement of respiratory efficiency? PLUGS”? Tidal Volume Frequency Timed Vital Capacity Inspiratory Reserve Volume Expiratory Reserve Volume The drive to breathe when one holds their breath is influenced largely by WP 0.55? the rising pressure of carbon dioxide in the arterial blood. the falling pressure of oxygen in the arterial blood. the rising pressure of carbon dioxide and falling pressure of oxygen in arterial blood. the neural drive from the rib cage. the rising pressure of nitrogen in the alveolar air. The “Breath Sound Check” developed at the University of Toronto is A. B. C. D. an indicator of the Ventilatory Threshold. 7 is an indicator that you do not need artificial respiration. a measure of airway resistance. a fitness measurement when combined with Expiratory Reserve Volume. Which of the following statements is/are true? A. B C. D The “Talk Test” developed at the University of Toronto provides a “lid” so that one can tell if the exercise is “anaerobic.” The “Talk Test” functions because the drive to breathe increases with anaerobic metabolism and affects expiration. The “Talk Test” functions because the drive to breathe increases with aerobic exercise and affects inspiration which interrupts speech. The “Talk Test” enables the public to determine if they are anaerobic or aerobic while exercising (jogging, cycling, skating). 11. A higher oxygen pressure in the alveolar air facilitates A. carbonic acid in the blood changing to C02 and water B. C02 and water in the blood changing to carbonic acid C. A shorter breath holding time D. Increased haemoglobin production Renal Physiology - Mavrogiannis 12. Renal tubules normally reabsorb: (Select the one false statement) more water every hour than the entire plasma volume all filtered HCO3' in respiratory acidosis all filtered amino acids all filtered plasma proteins more potassium than chloride P153097? 13. Aldosterone (Select the one true statement) A. is a steroid hormone secreted by the adrenal medulla B. production ceases following removal of the kidneys, and juxtaglomerular cells C. production decreases in treatment with drugs which block angiotensin converting enzyme D. secretion results in increased potassium reabsorption by the nephron E. secretion results in a rise in urinary pH 14. Given: Pressure at the glomerulus capillary (Fee) = 56 Pressure in Bowmans capsule (PBC) = 14 Oncotic pressure in Bowmans capsule (use) = 0 Oncotic pressure in the glomerulus capillary (nae) = 32 The calculated net glomerular filtration pressure is: A. +10 B. 0 C. -10 D. +38 E. +74 15. Select the one false statement: A. people suffering from diabetes insipidus have increased plasma osmolarity B. depending on location in the kidney tubule sodium ion reabsorption may be linked to hydrogen ion transport C. rennin release is stimulated by a decrease in the GFR D. angiotensin II stimulates the release of ADH E. increased bicarbonate reabsorption occurs to compensate for an increase in blood pH 16. If blood pH increases, which of the following may increase to compensate? (Select the one true statement) A. bicarbonate synthesis in the distal tubule B. bicarbonate reabsorption C. IF secretion D. none of the above 17. Trace the path of an erythrocyte through the kidney circulation: afferent arteriole efferent arteriole glomerular capillary vasa recta renal vein 99.0.62» A c,b,d,a,e B. a,c,b,d,e C. b,c,d,e,a D. c,a,b,d,e E. e,a,c,b,d Blood and Immune System — Perumalla 18. Identify the one incorrect statement regarding leukocytes: A. Neutrophils are granulocytes and monocytes are agranulocytes B. Normally, about 60% of the leukocytes present in circulation are lymphocytes C. Neutrophils exhibit diapedesis, chemotaxis and phagocytosis D. Acute bacterial infection can result in a rapid increase in neutrophils in the circulating blood E. Basophils are mostly tissue bound 19. Identify the one incorrect statement. A. The fibrinogen concentration in serum is lower than in plasma B. Albumin is the major contributor to plasma oncotic pressure C. Both the intrinsic and extrinsic pathways converge on factor X for the activation of prothrombin D. Platelets contain contractile proteins E. Vitamin K is necessary for blood clot formation because it activates the extrinsic pathway 20. Regarding compatibility of blood transfusion (one incorrect) O t b/ \ \d/ t A AB In the diagram above: A “a” is a universal donor B. “b” is most likely blood type A C. “c” is most likely blood type B D. “d” has both A and B antibodies in the plasma 21. Identify the one incorrect statement regarding the inflammatory response: Basically, it is specific, not general Neutrophils exit from blood vessels and are followed by monocytes Tissue macrophages are primary players Phagocytosis occurs in the inflammatory response Cytotoxic T cell does not play a role in inflammatory response mpow> 22. Identify the one incorrect statement A. B. C. D. E. Passive immunity results from the injection of antibodies against the agent to which immunity is sought A secondary response to immunization occurs more rapidly, is more substantial and lasts longer than a primary response People who lack T cells reject tissue grafts more strongly and are less susceptible to cancers Interferon is a cellular protein that plays a role in inhibition of viral growth and replication The complement cascade can be activated by binding to antibodies on bacterial cells Cardiovascular - Kee 23. 24. Which of the following statement regarding the electrical activity of the cardiac contractile cells is TRUE? A. FLU 0'!” During Phase 0, impulse from the SA node arrives and depolarizes the membrane which triggers the opening of the voltage-gated Na channels to increase the flow of Na ions into the cell. During Phase 1, the Na channels that were opened in phase 0 start to inactivate leading to decreased permeability of Na ions. During Phase 2, most of the K channels that were closed in Phase 1 stay closed and most of the Ca channels that opened in Phase 1 remain open. During Phase 3, both the Ca and K channels start to open. During Phase 4, permeability of Na, Ca, and K are at their resting values. At the onset of early diastole (Phase 4 of the cardiac pumping cycle), the ventricular myocardium is relaxing and is referred to as ventricular valve is wpow> . During this phase, the atrio- and the semilunar valve is Isovolumetric contraction, open, closed Isovolumetric contraction, open, open Isovolumetric relaxation, open, closed Isovolumetric relaxation, open, open Isovolumetric relaxation, closed, closed 25. 26. 70 Start of atrial contraction T Start of atrial contraction The above diagram depicts the changes in ventricular volume. What is the stroke volume as represented by the above diagram? A. B C D. E 60 ml, which is the difference between the end—diastolic volume (130 ml) and end-systolic volume (70 ml). 60 ml, which is the difference between the end—systolic volume (70 m1) and end- diastolic volume (130 ml). 130 ml, which is the difference between the end-diastolic volume (130 ml) and end—systolic volume (0 ml). 130 ml, which is the difference between the end-systolic volume (130 m1) and end-diastolic volume (0 ml). None of the above. Last week, Jack stood up very quickly and felt dizzy. This condition is called orthostatic hypotension. What caused Jack’s dizziness? A. B C. D Force of gravity increased the pressure in the blood of the lower veins, leading to venous pooling causing a reduced cardiac output. Force of gravity caused an increase in the parasympathetic nerve activity, leading to venous pooling causing a reduced cardiac output. Force of gravity caused a decrease in the sympathetic nerve activity, leading to venous pooling causing a reduced cardiac output. Due to low compliance of the veins, quickly standing up caused the blood in the central veins to drain to the lower veins, causing a reduced cardiac output. None of the above. Mean arterial pressure Resistance Blood flow N .4 w 3; 3 GI Brain Reflex Control Hemorrhage compensation -I— a, - -l."= The above diagram depicts the events that occur during and following hemorrhage. Following reflex compensation, the mean arterial pressure is returned to near normal values, what happens to both the resistance and blood flow to the brain and the GI tract following reflex compensation? A. Resistance to the brain goes down and resistance to the GI tract goes down, resulting in increased blood flow to the brain and increased blood flow to the GI tract. Resistance to the brain remain constant and resistance to the GI tract goes up, resulting in increased blood flow to the brain and decreased blood flow to the GI tract. Resistance to the brain remain constant, resistance to the GI remain constant resulting in increased blood flow to the brain and increased blood flow to the GI tract. Resistance to the brain goes up, resistance to the GI tract goes down resulting in decreased blood flow to the brain and increased blood flow to the GI tract. Resistance to the brain goes up and resistance to the GI tract goes up, resulting in deceased blood flow to the brain and decreased blood flow to the GI tract. 28. 29. 30. 31. Following rigorous exercise routine, Jane noticed that her mean arterial pressure did not change very much, even though her cardiac output was raised substantially. Why didn’t Jane’s mean arterial pressure go up? A. Due to increase in stroke volume. B. Due to increase in end-diastolic volume. C. Due to increase in heart rate. D. Due to decrease in total peripheral resistance. E. Due to decrease in muscle blood flow. Endocrinology Dr. Banks The pituitary is also known as the A. adenohypophysis B. hypophysis C. neurohypophysis D. infundibilum E. pineal gland The target cell for ADH with respect to its action on water reabsorption at the kidneys is the A. osmoreceptor B. tubule cell C. collecting duct D. principal cell E. granule cell Colloid contains all the essential components for the synthesis of the thyroid hormones. These include: A. thyroglobulin, tyrosine, iodide B. thyroglobulin, iodide, enzymes C. enzymes, TSH, TRH D. TRH, TSH E. B & D 10 32. 33. 34. All of the following are possible steps in the synthesis of the thyroid hormones, EXCEPT: A. B. C. D. E. the phagosome containing the thyroid hormones still bound to thyroglobulin fuses with a lysosome adjacent tyrosine residues couple tyrosine residues are iodinated coupling of adjacent tyrosine residues that have been iodinated at two sites each will yield the precursor to T3 following coupling of adjacent tyrosine residues, the precursor hormones may be stored in colloid for several months Based on the actions of the thyroid hormones presented in class, which of the following would be an expected symptom associated with adult onset hyperthyroidism: WPOF’?’ weight loss decreased blood pressure mental dullness weight gain linear growth Aldosterone is involved in the regulation of plasma osmolarity by stimulating the movement of sodium between the tubular filtrate and the plasma. The mechanism of action for this effect is achieved by: WUOF’?’ stimulation of insertion of sodium channels into the basolateral membrane and sodium/potassium pumps into the apical membrane stimulation of insertion of sodium channels into the apical membrane and sodium/potassium pumps into the basolateral membrane stimulation of reabsorption of potassium and secretion of sodium stimulation of the nuclear receptor for aldosterone stimulation of sodium/potassium pumps into the apical membrane and sodium channels into the basolateral membrane 11 35. 36. 37. 38. What is the hypothalamic hormone that results in stimulation of the release of the sex hormones from the gonads? A. gonadotropin B. GnRH C. LH D. FSH E. inhibin Sertoli cells secrete and inhibin, testosterone LH, FSH testosterone, LH androgens, inhibin inhibin, androgen-binding protein WUOW? Which of the following statements regarding the uterine cycle is NOT true? A. it has three phases B. the menstrual phase is precipitated by a rapid drop in progesterone and estrogen that is associated with degeneration of the corpus luteum C v the proliferative phase is associated with rejuvenation of the blood supply to the endometrium D. the changes of the proliferative phase occur in response to an increasing concentration of progesterone produced by the maturing follicle E the changes of the secretory phase occur as a preparation for a possible pregnancy Which of the following hormones directly results in the transformation of the remnant of the follicle to the corpus luteum? A. FSH B. LH C. estrogen D. GnRH E. progesterone 12 New material 0.5 marks/question Neurophysiology - Hutchison 39. A collection of neuron cell bodies located outside the brain and spinal cord is called a: A. tract B. nerve C. ganglion D. nucleus 40. The myelin sheaths of peripheral axons are formed from: A. oligodendrocytes B. Schwann cells C. microglia D. astrocytes 41. Which of the following statements concerning the cranial nerves is correct: A. cranial nerve I is important for visual sensation B. cranial nerve 11 controls movements of the eyes C. cranial nerve V has both motor and sensory functions D. cranial nerve X contains only sensory afferents from the viscera 42. List in order the functions of the neuron with the region of the neuron listed on the left. __ distribute the output to synaptic sites on next neuron, 1. dendrite __ propagate the output pattern of the neuron as spikes, 2. cell body _ input region, receiving area of neuron 3. axon hillock __ oscillations and intrinsic spiking activity 4. axon terminal A. 1, 2, 3, 4 B. 4, 3, 1, 2 C. 4, 3, 2, 1 D. 3 4 1, 2 q u 13 43. A nerve fibre codes for the strength of a stimulus by the: A. amplitude of action potentials B. frequency of action potentials C. duration of each action potential D. velocity of the action potential 44. The all—or—nothing law of neurophysiology states that: A. the amplitude of the action potential is constant B. the frequency of action potentials is constant C. the velocity of action potentials is constant D. the duration of action potentials is constant 45. Which of the following cells are capable of producing action potentials A. only neurons B. only myofibrils C. hair cells D. both A. and B 46. The electrical excitation of a muscle fibre most directly causes: A. cross-linking of the thick and thin filaments B. hydrolysis of ATP C. release of calcium from the sarcoplasmic reticulum D. sequestration of calcium back into the sarcoplasmic reticulum 47. Which statement best describes the twitch in muscle physiology? A. a single muscle fibre, when stimulated, will always contract maximally B. a muscle will always contract maximally when stimulated C. thick and thin filaments when stimulated, always contract maximally D. the rapid contraction of the gastrocnemius muscle is a good example of a twitch- like response 48. Which of the following statements concerning fast glycolytic fibres is true. A. they generally appear red in colour due to high myoglobin content B. they are resistant to fatigue C. they contain numerous mitochondria but relatively little myosin ATPase D. none of the above 14 49. The ventral roots of spinal nerves contain: A. cell bodies of sensory neurons B. motor fibres only C. sensory fibres only D. both motor and sensory fibres 50. Complete the following to make a correct statement concerning audition. The scala vestibuli and scala tympani are connected to each other at: A. the round window B. the oval window C. the helicotrema D. they are not connected; they are separate structures 51. Which of the following concerning NMDA receptors is incorrect: A. long term changes in membrane characteristics may follow NIVIDA activation B. NMDA receptor activation leads to conductance of Na+’ K+ and Ca2+ ions C. at normal resting potential the channel is blocked by manganese ions D. NMDA receptor has binding sites for 2 glutamate molecules The next 3 questions concern the following list of transmitters: 1. acetylcholine 2. noradrenaline 3. dopamine 4. nitric oxide 5. enkephalin 6. GABA 52. Which of them undergo rapid re-uptake after release into the synapse? A. 1, 2, 3 B. 2, 6 C. 2, 3, 6 D. 1,4,5 53. Which of the list are most likely to be broken down in the synapse? 15 54. 55. 56. 57. 58. Which of the list are most involved in emotions, mood and motor activation? Pick the incorrect statement concerning the nicotinic acetylcholine receptors. A. B. C. D. They are considered typical examples of ionotropic receptors. They are the primary receptor at the neuromuscular junction. At normal resting potential this channel is open but blocked by magnesium. Activation of this receptor leads to influx of N a+ ions. Pick the incorrect statement concerning the mechanism of hearing. A. B. C. D. Light passes through the layer of rods and cones The base of the cochlea has an area of resonance for higher auditory frequencies. Inward movement of the stapes produces outward movement of the round window. Hair cells are supported by the tectorial membrane and the shearing force of the basilar membrane produces action potentials The chemical composition of the fluid in the scala media is dependent on the stria vascularis _C(B ,before; A, after) passing through the layer with retinal ganglion cells, whose axons leave the back of the eye at the (F, fovea; M, macula, D, optic disk). A. B. C. D. Information from the left visual field of the right eye and the B,D ,F ,M D >>> visual field of the side of the visual cortex. (R = right L = left) left eye project to the A. R,R B. R, L C. L, R D. L,L 16 59. 60. 61. 62. Pick the correct statement concerning muscle contraction A. muscle cells generate receptor potentials that travel through the T-tubules B. at the neuromuscular junction muscarinic cholinergic receptors bind acetylcholine C. calcium release from the T—tubules is necessary for muscle contraction D. the time required for calcium to distribute and then clear from the muscle is the major reason for the production of fused tetanus Parkinson’s disease is associated with an insufficient number of neurons that use the transmitter. . . A. dopamine B. L—dopa C. noradrenaline D. enkephalin Mechanoreceptors in the joints and muscles inform the CNS about the body’s position in space. This type of sensation is referred to as (one correct): A. kinesthesia B. paraesthesia C. nociception D. proprioception Pick the correct statement concerning ascending sensory pathways: the inferior colliculus is a relay nucleus in the auditory pathway the medial geniculate is a relay on the visual pathway the superior colliculus is a relay nucleus in the visual pathway the lateral geniculate pow» Gastro-Intestinal Tract Physiology - K. Bandali 63. Which of the following is CORRECT? The digestive system includes a tube that extends from the mouth to the anus. The digestive system includes organs that food does not actually enter. The digestive system shares some structures with the respiratory system. A and B are correct. A, B and C are correct. £11,505”? 17 64. 65. 66. 67. 68. Which of the following is NOT part of the alimentary canal? A. tongue B. pharynx C. esophagus D. stomach E. small intestine Primary site of absorption in the GI system is: A. large intestine B. small intestine C. stomach D. esophagus E. mouth Which of the following is NOT an accessory organ of digestion? A. a tooth B. the appendix C. the liver D. the gall bladder E. the pancreas Hydrolysis of large biological molecules into smaller ones that can be absorbed by cells is A. ingestion B. mechanical digestion C. chemical digestion D. secretion E. propulsion The mucosa of the GI Tract (alimentary canal) is composed of 3 layers: mucous epithelium, the lamina propria and the muscularis mucosae. lines the lumen of the alimentary canal. includes an inner sheet of circular muscle fibers and an outer layer of longitudinal fibers. A and B are correct. A, B and C are correct. .mp man? 18 69. A lab group is sent to the cafeteria to do an experiment. The instructions direct each student to obtain a regular saltine cracker and to chew it 25 times before swallowing. The students are to observe and record the initial and final tastes of the cracker. Most students record that the cracker initially tastes salty, but then tastes sweet. Which of the following correctly explains the students’ observations? The salt on the crackers dissolved slowly in saliva and is detected by the taste buds over time. Salivary amylase digested the cracker’s starch into sugars that could be then be tasted. Lingual lipase digested the cracker’s fat into sugars that could then be tasted. A and B are correct. A and C are correct. mp0 w > 70. Fat absorption involves: emulsification lecithin bile salts formation of micelles all of the above menu? 71. About 1/4000 babies are born with esophageal atresia, a condition in which the esophagus does not connect to the stomach. Many of these infants also have a fistula, or opening, that connects the esophagus to the trachea. How will esophageal atresia with tracheosesophageal fistula affect an infant? The infant will not be able to pass milk to its stomach. The infant will not be able to absorb nutrients from milk. The infant will only have difficulties absorbing nutrients. A and B are correct. 'A, B and C are correct. mung? 72. Which of the following is NOT a function of the stomach? A. serves as the primary absorption site for most nutrients B. receives the bolus from esophagus C. delivers chyme to the duodenum D. performs both mechanical and chemical digestive processes E. produces HCl, pepsinogen and gastric lipase 19 73. 74. 75. 76. 77. The exit of the stomach, which is sometimes stenosed (narrowed) in infants, is the The digestive juice that contains enzymes capable of digesting all three major food WCOW? cardia pylorus fundus body rugae groups is: A. biliary B. pancreatic C. gastric D. esophageal E. salivary An individual suffering from hyposecretion by gastric chief cells would have WUOW? inadequate amounts of intrinsic factor and HCl. excessive amounts of intrinsic factor and HCl. inadequate amounts of pepsinogen. excessive amounts of pepsinogen. inadequate amounts of mucus. Gastrin functions to: WPOW? inhibit the production of hydrochloric acid increase the secretions of gastric glands change pepsin into pepsinogen initiate the cephalic phase of gastric digestion increase peristalsis in the stomach The “cephalic” phase of gastric secretion: A B. C. D E involves a decrease in the release of gastrin increases the activation of pepsinogen (to pepsin) is triggered by taste, sight, thought or smell of food decrease secretion of HCl directly inhibits the conversion of pepsinogen to pepsin 20 Circadian Rhfihms— Dr. Martino 78. Circadian rhythms are important for cardiovascular physiology in healthy animals. Which of the following statements is false? A. Animals exhibit 24 hour rhythms in heart rate and blood pressure. B. In humans (diurnal animals), heart rate and blood pressure are increased in the day (light period) and decreased at night (dark period). C. In mice (nocturnal animals), heart rate and blood pressure are increased in the day (light period) and decreased at night (light period). D. none of the above. 79. Physiologic rhythms play an important role in precipitating early morning onset of acute cardiovascular events such as heart attacks or strokes. Which statement provides the best overall physiologic explanation for why this is so? A. Early in the morning blood pressure rises, there is increasing left ventricular stroke work (the heart works harder), which has implications for the fracturing and/or rupturing of plaques (they are more likely to break early in the morning). B. Early in the morning the platelets tend to increase in aggregability, clotting increases, and this has implications for aterial thrombosis (clot formation tends to be larger and more aggressive). C. Early in the morning catecholamines increase and act on various systems including the vasculature, causing vasoconstriction, and intra-arterial pressure to rise. D. The events in A, B, C combine leading to early morning onset of acute cardiovascular events. 80. The circadian system regulates physiologic rhythms. Which statement most accurately describes this process? A. The presence or absence of light is detected by special retinal cells, which then transmit signals down the retinal—hypothalamic tract (RHT) to the hypothalamus. B. The presence or absence of light is detected by rod and cones cells, which then transmit signals down the retinal-hypothalamic tract (RHT) to the hypothalamaus. C. The signals are received by the suprachiasmatic nucleus (SCN) in the hypothalamus, and depending on whether they are received day versus night they set off different signal cascades. D. Statements A and C combined. 21 81. How does the suprachiasmatic nucleus (SCN) regulate rhythms in peripheral organs like the heart? A. Signals from the SCN are sent out to other regions of the brain and to body organs via neural and hormonal outputs. B. There are direct neural connections between the SCN and each body organ. C. The body organs have their own ability to “sense” the presence or absence of light and thus set own rhythms. D. Body organs are not regulated by the SCN. 82. The following statement best describes the molecular circadian clock mechanism. A. It is a transcription (mRNA) feedback loop which cycles every 24 hours to keep time. B. It is a translation (protein) feedback loop which cycles every 24 hours to keep time. C. It is a transcription and translation feedback loop which cycles every 24 hours to keep time. D. No one knows yet how the molecular clock mechanism works to keep time. 83. Which of the statements on applying circadian biology principles to humans is true? A. Shiftwork, sleep disorders, and jet lag are all examples of how rhythms might be disturbed in humans. B. Circadian rhythms are useful in translational medicine such as for the development of biomarkers, and chronotherapy (timing of therapy). C. Both A and B are true. D. Both A and B are false. Physio ex 84. BAPNA is a synthetic protein that: is an enzyme that promotes the conversion of inactive proenzymes is a key regulatory molecule important in the digestion of protein into absorbable amino acids is colorless and transparent in solution but becomes yellow if digested by a digestive enzyme acts as a hydrolase to accelerate the addition of water to food molecules C andD .mp0!» 22 85. Salivary amylase is a digestive enzyme that DOES NOT breakdown: A. com B. potatoes C. glycogen D. cellulose E. C and D 86. Pepsin is a digestive enzyme that works optimally at a pH of A. 2 B. 7 C. 9 D. 1 1 E. none of the above 87. Regarding a nerve action potential (AP) only one statement is correct: A. AP observed in the physioEx by electrical and chemical stimulation was different in size and shape AP was not produced when a threshold was reached increase in stimulus voltage increased AP threshold AP was produced by applying hydrochloric acid to the nerve The term AP can be interchangeably used with term compound action potential .mp0?” 88. The conduction velocity is fastest in: A. Large diameter axon. B. Myelinated nerve. C. A + B ' D. Unmyelinated nerve. E. A + D 89. The effect of lidocaine on the action potential was tested. Lidocaine: most likely blocked potassium channels _ did not affect nerve propagation because it works on the synaptic ends of the nerve most likely blocked sodium channels increased the conducting velocities in earthworm affects only unmyelinated nerves F1190 PU? Total marks 37*1+52*0.5= 63 marks 23 ...
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This note was uploaded on 04/04/2011 for the course PHYSIOLOGY 200 taught by Professor Kee during the Winter '10 term at Waterloo.

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PSL201 Final Exam 2007 - Name Student Number Questions...

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