Physiology | Set 3

1. With regard to the metabolism of carbohydrates:

A. in the absence of liver glycogen stores, glycogen administration does not cause hyperglycaemia

B. glucocorticoids have a minor effect on gluconeogenesis

C. growth hormone causes increased use of glucose for energy

D. glucose is absorbed by most cells by active sodium glucose co-transport

E. during starvation, stores last for less than 24 hours

Correct : E. during starvation, stores last for less than 24 hours

2. With regard to lipid metabolism:

A. only HDL is formed in the liver

B. fatty acids in the plasma form 1:1 complexes with albumin

C. plasma cholesterol levels rise considerably with an increase in daily ingestion

D. free fatty acids are metabolised in preference to glucose in a non-exercising individual

E. utilisation of fatty acids is stimulated by glucocorticoids

Correct : E. utilisation of fatty acids is stimulated by glucocorticoids

3. With regard to carbohydrate metabolism:

A. the normal fasting glucose is from 3.9 to 11.0mmol/L

B. glucose is phosphylated in cells to glucose-6-phosphate by phosphoenol-pyrunate carboxykinase

C. glycogen, the storage form of glucose, is only in the liver and skeletal muscle

D. glucose can be converted to fats through acetyl CoA which is irreversible

E. none of the above

Correct : D. glucose can be converted to fats through acetyl CoA which is irreversible

4. Which statement regarding glucagon is INCORRECT?

A. it is used as an antidote in symptomatic beta blocker overdosage

B. it is synthesised in the A cells of the pancreatic islets and in small intestinal mucosal cells

C. its major site of metabolism is in the plasma

D. it is synthesised in common with glicentin

E. the exogenous glucagon is associated with nausea and vomiting

Correct : C. its major site of metabolism is in the plasma

5. Which of the following is NOT an action of somatostatin?

A. it inhibits glucagon secretion

B. it is a synaptic transmitter in the retina

C. it inhibits insulin secretion

D. it increases contraction of the gallbladder

E. it inhibits pancreatic polypeptide secretion

Correct : D. it increases contraction of the gallbladder

6. Glucagon increases the secretion of all of the following EXCEPT:

A. catecholamines from a phaeochromocytoma

B. atrial natriuretic peptide

C. growth hormone

D. insulin

E. calcitonin from a medullary carcinoma of the thyroid

Correct : B. atrial natriuretic peptide

7. Regarding the actions of glucagon, which of the following is INCORRECT?

A. it increases blood lactate level

B. it activates hormone-sensitive lipase

C. it has a positive inotropic effect on myocardium

D. large amounts cause intestinal relaxation

E. it decreases renal tubular sodium reabsorption

Correct : A. it increases blood lactate level

8. Which of the following does NOT increase pancreatic polypeptide secretion?

10. Regarding the action of glucagon on the liver, which of the following is INCORRECT?

A. it causes glycogenolysis via activation of adenylate cyclase

B. it decreases metabolism of glucose-6-phosphate

C. it causes glycogenolysis via activation of phospholipase C

D. it increases gluconeogenesis from available amino acids

E. it decreases ketone body formation

Correct : E. it decreases ketone body formation

11. Regarding the synthesis of thyroid hormones, which statement is INCORRECT?

A. iodine undergoes rapid oxidation following entry to thyroid cells

B. the “iodine pump” is the major source of iodine for hormone synthesis

C. TSH increases iodine uptake by the thyroid gland

D. thiocyanate and ouabain decrease iodine uptake by the thyroid gland

E. it involves iodination of thyrosine residues in thyroglobulin

Correct : B. the “iodine pump” is the major source of iodine for hormone synthesis

12. Which of the following does NOT inhibit secretion of glucagon?

13. Which plasma protein has the greatest thyroxine binding capacity?

14. Which of the following does NOT increase secretion of glucagon?

15. Which plasma protein has the greatest thyroxine-binding affinity?

16. Regarding insulin, which statement is INCORRECT?

A. it consists of two polypeptide chains linked by two disulphide bridges

B. the majority of exogenous insulin is metabolised by the liver

C. it is not the only molecule responsible for insulin-like activity in the blood

D. it increases intracellular potassium concentration

E. exercise increases the affinity of its receptors for insulin

Correct : B. the majority of exogenous insulin is metabolised by the liver

18. Which of the following hormones does NOT increase the hepatic output of glucose?

20. Regarding the action of insulin on adipose tissue, which of the following is INCORRECT?

A. it induces lipoprotein lipase which actively hydrolyses triglyceride from circulating lipoproteins

B. it reduces circulating free fatty acids

C. it promotes triglyceride storage in adipocytes

D. it directly inhibits intracellular lipase

E. its effects appear to involve phosphorylation of lipases

Correct : E. its effects appear to involve phosphorylation of lipases

22. Which glucose transporter is responsible for insulin-mediated glucose uptake in striated muscle and adipose tissue?

23. Where are the receptors located by which thyroid hormones mediate most of their effects?

24. Regarding the action of insulin in skeletal muscle, which of the following is INCORRECT?

A. it decreases protein catabolism

B. it induces glucogen synthase

C. it decreases ketone uptake

D. it increases amino acid uptake

E. it decreases the release of gluconeogenic amino acids

Correct : C. it decreases ketone uptake

26. Which glucose transporter is responsible for the facilitated diffusion of glucose into pancreatic B cells?

27. Regarding the effects of thyroid hormones, which of the following does NOT occur?

A. it increases metabolic rate

B. it directly stimulates sodium-potassium ATPase

C. it increases protein and fat catabolism

D. it increases body temperature

E. it increases cerebral oxygen consumption

Correct : E. it increases cerebral oxygen consumption

28. Regarding the action of insulin on the liver, which of the following is INCORRECT?

A. it increases gluconeogenesis

B. it decreases glycogenolysis

C. it increases synthesis of triglyceride and VLDL

D. it decreases cyclic AMP

E. it increases phosphate uptake

Correct : A. it increases gluconeogenesis

29. Which statement regarding the thyroid gland and its hormones is INCORRECT?

A. thyroid hyperactivity is associated with an increase in plasma catecholamines

B. iodide trapping by thyroid cells is an active process

C. thyroid hormones enter cells by diffusion across the cell membrane

D. thyroid hormones cause an increase in 2,3 - DPG

E. thyroid hormones increase growth hormone secretion

Correct : A. thyroid hyperactivity is associated with an increase in plasma catecholamines

30. Regarding the secretion of insulin, which statement is INCORRECT?

A. insulin is not required for glucose to enter pancreatic B cells

B. it involves closure of ATP-sensitive potassium channels

C. it is a biphasic process involving two pools of insulin

D. it involves opening of voltage-sensitive calcium channels

E. glucose enters pancreatic B cells by combining with glut 4

Correct : E. glucose enters pancreatic B cells by combining with glut 4

31. Which of the following do NOT increase TSH secretion?

33. Which of the following does NOT increase intestinal calcium absorption?

34. Which of the following does NOT stimulate insulin secretion?

35. Which of the following does NOT decrease intestinal calcium absorption?

36. Regarding the insulin receptor, which statement is INCORRECT?

A. it is present even in cells which do not increase their glucose intake in response to insulin

B. insulin binds to the β subunit on the outer surface of the cell membrane

C. it is a tetramer of two α and two β subunits

D. the binding of insulin decreases the activity of tyrosine kinase on the intracellular end of the receptor

E. the complex of insulin and receptor become internalised by the cell

Correct : B. insulin binds to the β subunit on the outer surface of the cell membrane

37. Which of the following does NOT increase plasma calcium?

38. Which of the following is NOT associated with an increase in erythropoietin secretion?

39. Which of the following does NOT increase parathyroid hormone secretion?

40. Regarding erythropoietin, which statement is INCORRECT?

A. its secretion increases within minutes to hours in response to hypoxia

B. it causes pro-erythroblasts to mature more rapidly into erythrocytes

C. the spleen and salivary glands secrete, but don’t synthesise it

D. it inhibits apoptosis in erythroid stem cells

E. the adult liver is able to synthesise enough for normal erythropoiesis in the absence of both kidneys

Correct : E. the adult liver is able to synthesise enough for normal erythropoiesis in the absence of both kidneys

41. Which statement regarding parathyroid hormone (PTH) is INCORRECT?

A. it is continuously secreted by the parathyroid glands

B. it is synthesised and secreted by the oxyntic cells

C. it is rapidly cleaved in the Kupffer cells of the liver

D. it increases osteoclasts activity in bone

E. it increases formation of 1,25-dihydroxycholecalciferol

Correct : B. it is synthesised and secreted by the oxyntic cells

42. Regarding endothelins, which statement is INCORRECT?

A. they can cause dose-dependent vasoconstriction in most vascular beds

B. they activate phospholipase C

C. they are structurally similar to vasoactive intestinal contractor

D. they have negative inotropic effect

E. there are low concentrations present in blood

Correct : D. they have negative inotropic effect

43. Which statement regarding calcitonin is INCORRECT?

A. it is secreted by parafollicular cells of the thyroid gland

B. it inhibits osteoclastic bone resorption

C. total thyroidectomy is usually associated with hypercalcaemia

D. it decreases renal tubular calcium and phosphate reabsorption

E. it is only secreted when plasma calcium concentration exceeds 9.5mg/100ml

Correct : C. total thyroidectomy is usually associated with hypercalcaemia

44. Regarding atrial natriuretic peptide, which statement is INCORRECT?

A. cardiac innervation is not required for secretion to occur

B. its action is terminated by receptor-mediated endocytosis

C. its filtration fraction is decreased

D. it is secreted by heart, lung and brain

E. glucocorticoids increase its secretion

Correct : C. its filtration fraction is decreased

45. Regarding the role of vitamin D in calcium metabolism, which of the following is INCORRECT?

A. it increases renal tubular calcium and phosphate reabsorption

B. it causes an increase in synthesis of calcium-binding protein

C. it increases bone resorption

D. it decreases bone formation

E. it increases intestinal calcium and phosphate absorption

Correct : D. it decreases bone formation

46. Atrial natriuretic peptide decreases formation of all of the following EXCEPT:

47. Which of the following does NOT increase aldosterone secretion?

A. constriction of the IVC in the thorax

B. ACTH

C. surgery

D. hyperkalaemia

E. lying supine from the standing position

Correct : E. lying supine from the standing position

48. Which of the following does NOT increase secretion of atrial natriuretic peptide?

A. β-adrenoceptor agonists

B. immersion in water up to the neck

C. exercise

D. endothelin

E. changing from erect position to supine

Correct : A. β-adrenoceptor agonists

49. Regarding aldosterone, which statement is INCORRECT?

A. it responds to changes in plasma sodium more strongly than changes in plasma potassium

B. it is only synthesised in the zona glomerulosa of the adrenal cortex

C. its main action is to increase the synthesis of sodium-potassium pumps

D. angiotensins II and III have about equal mineralocorticoid stimulating activity

E. it acts via a cytoplasmic receptor that has equal affinity for cortisol

Correct : A. it responds to changes in plasma sodium more strongly than changes in plasma potassium

50. A 15-year-old girl suffers from a malabsorption syndrome characterised by the malabsorption of fat. In which vitamin is she MOST likely to be deficient?

51. Thyroxine (T4):

A. secretion is regulated by positive feedback at the hypothalamus

B. is transported principally by albumin in the blood

C. causes increased LDLD in plasma

D. is physiologically more active than T3

E. increases β receptors in the cardiovascular system

Correct : E. increases β receptors in the cardiovascular system

52. Regarding insulin:

A. it increases amino acid uptake

B. its absorption is not affected by the site of injection

C. it causes reduced K+ uptake by cells

D. it increases protein catabolism

E. it is secreted by the α cells in the islets of Langerhan

Correct : A. it increases amino acid uptake

53. The content of chylomicrons includes:

A. aproprotein E and aproprotein A

B. cholesterol 30%, protein 20%, triglyceride 50%

C. lethicin 10%, cholesterol 25%, triglyceride 65%

D. protein 2%, cholesterol 5%, triglyceride 90%

E. the enzyme protein phospholipase

Correct : D. protein 2%, cholesterol 5%, triglyceride 90%

54. Regarding calcium metabolism:

A. the adult human body contains 15% of its body mass as calcium

B. calcium is passively absorbed from the intestinal brush border

C. oestrogen inhibits osteoclasts

D. TNF inhibits osteoclasts

E. corticosteroids stimulate osteoblasts

Correct : C. oestrogen inhibits osteoclasts

55. Regarding cellular components:

A. peroxisomes are larger than lysosomes

B. pH of lysosomes is higher than the rest of the cytoplasm

C. microfilaments are hollow

D. myosin 1 molecules are characteristically found in muscle cells

E. microfilaments are made up of actin

Correct : E. microfilaments are made up of actin

58. Given that a person weighs 60kg and their haematocrit is 40%, their total blood volume is:

63. Regarding mitochondria:

A. genome inheritance is strictly maternal

B. the citric acid cycle occurs at the outer membrane

C. the space between the two membranes is called the matrix

D. the mutation rate for mitochondrial DNA is less than for nuclear DNA

E. involutions of the outer membrane are called cristae

Correct : A. genome inheritance is strictly maternal

64. Which volume of distribution is evaluated with which substance?

65. Which is correct?

A. blood volume is 8% total body weight

B. 2/3 total body weight is ECF

C. 75% of ECF is blood plasma

D. water content of lean tissue is 25%

E. total body water increases with increasing age

Correct : A. blood volume is 8% total body weight

66. For mitochondria, which is TRUE?

A. NADH-DH, 5DH, bc, cox synthesise ATP

B. the matrix is between the inner and outer mitochondrial DNA

C. mitochondrial DNA is not transmitted paternally

D. 99% of mitochondrial proteins are encoded by mitochondrial DNA

E. ATP synthetase is powered by an electron gradient

Correct : C. mitochondrial DNA is not transmitted paternally

67. Which is TRUE?

A. the cytoskeleton is composed of hydroxyapatites

B. the mitotic spindle is composed of actin microtubules

C. myosin is the most abundant protein in cells

D. colchicine stabilises microtubules preventing organelle movement

E. actin-myosin interaction allows cells to move

Correct : E. actin-myosin interaction allows cells to move

68. For the genome, which is TRUE?

A. the human genome encodes 3 X 109 genes

B. adenine binds to cytosine and guanine to thymine

C. uracil replaces thymine in RNA

D. 3% of DNA are introns

E. haploid DNA in germ cells is single stranded

Correct : C. uracil replaces thymine in RNA

69. For transmembrane movement, which is TRUE?

A. exocytosis requires Ca2+ and energy

B. Na+ -K+ -ATPase is an example of facilitated diffusion

C. amiloride activates epithelial Na+ channels

D. clathrin is essential for vesicle exocytosis

E. water can only enter cells via water channels

Correct : A. exocytosis requires Ca2+ and energy

70. For the Erlanger and Gasser classification, which is TRUE?

A. Sunday morning syndrome mainly affects C fibres

B. local anaesthetics primarily affect A fibres

C. preganglionic autonomic fibres are type B

D. C fibres have the largest diameter

E. B fibres are the least susceptible to hypoxia

Correct : C. preganglionic autonomic fibres are type B

71. For the glial cells, which is TRUE?

A. one schwann cell can myelinate up to 40 neurons

B. oligodenotocytes are the scavenger cells of the CNS

C. microglia are the scavenger cells of the PNS

D. there are up to three glial cells per neuron in the nervous system

E. protoplasmic astrocytesase found in grey matter

Correct : E. protoplasmic astrocytesase found in grey matter

72. For cardiac muscle, which is FALSE?

A. HERG really is the acronym for human ether-a-go-go related gene

B. intercolated discs are calcified structures within cardiac muscle cells

C. resting membrane potential is -90mV

D. cardiac muscle requires continuous supply of O2 to function

E. cardiac muscle action potential time decreases with increasing heart rate

Correct : B. intercolated discs are calcified structures within cardiac muscle cells

73. For neurotransmitters, which is TRUE?

A. acetylcholine is synthesised by true cholinesterase

B. atropine blocks muscarinic cholinergic receptors

C. catecholamines are formed from VMA (vanillylmandelic acid)

D. adrenaline has a higher affinity for α rather than β adrenergic receptors

E. dopamine is formed by COMT from tryptophan

Correct : B. atropine blocks muscarinic cholinergic receptors

74. Regarding body water, which is FALSE?

A. 1/3 total body weight is extra and 2/3 intra cellular

B. 60% of body weight is water

C. plasma is 8% and total blood 10%, of body weight

D. of extracellular fluid, 25% is vascular, 75% extravascular

E. interstitial fluid is 15% of body weight

Correct : C. plasma is 8% and total blood 10%, of body weight

75. Chemical composition, which is TRUE?

A. pH is the negative natural logarithm of [H+]

B. pH 5 to pH 6 involves tenfold increase in [H+]

C. pH remains 7.4 +/- 0.05 in ECF, stabilised by buffer

D. H2O and CO2 H2CO3 H+ and HCO3-, adding H+ shifts the equilibrium to the right, while adding ??? shifts it to the left

E. the Donnan effect does not contribute significantly to the balance of electrolyte between intra and extra vascular compartment

Correct : C. pH remains 7.4 +/- 0.05 in ECF, stabilised by buffer

76. Nerve fibres, which is FALSE?

A. 70% of energy requirement of nerves is used in maintaining polarity across the recytlemina by action of Na-K ATPase

B. metabolic rate of nerves doubles in max action

C. “C” type fibres are non-myelinated and include some of the sympathetic preganglionic fibres

D. “A” and “B” fibres are all myelinated

E. effects of local anaesthetic are maximal in “C” fibres

Correct : C. “C” type fibres are non-myelinated and include some of the sympathetic preganglionic fibres

77. Regarding skeletal muscle, which is FALSE?

A. metabolic rate of muscle may increase 100 times in maximal activity

B. muscle cells can be excited chemically, mechanically and electrically, to produce action potentials in the cell membrane

C. actin is a myosin-binding protein which is a molecular motor, converting ATP energy to monomers

D. mitochondria are packed in between myofibrils

E. T tubules occur over the junction of I and A bands

Correct : C. actin is a myosin-binding protein which is a molecular motor, converting ATP energy to monomers

78. More on muscles; which is TRUE?

A. skeletal muscle cells act as syncytram, though intercellular communications

B. some skeletal muscles are not subject to voluntary control

C. smooth muscle contains regularly discharging pacemaker

D. a variant of smooth muscle is found in the eye, which resembles skeletal muscle

E. cardiac muscle does not contain regular striation

Correct : D. a variant of smooth muscle is found in the eye, which resembles skeletal muscle

79. More on muscles; which is FALSE?

A. T tubules are extensions of extracellular space

B. “cystems’ of SR are in contact with T-tubules

C. myosin molecules combine to form thick filaments while actin, tropomyosin, and the troponins the t…..

D. an individual muscle cell is a myofibril, containing myofilaments

E. the sarcolemnia transmits action potentials

Correct : D. an individual muscle cell is a myofibril, containing myofilaments

80. In muscle construction, which is TRUE?

A. only contraction is energy requiring, not relaxing

B. sequestering of Ca2+ causes separation of actin-myosin bands and muscle relaxation

C. ATPase clefts are on the tips of the myosin beads

D. ryanodine receptors are voltage gated Ca2+ chains

E. Troponin T inhibits the interaction of actin and myosin

Correct : B. sequestering of Ca2+ causes separation of actin-myosin bands and muscle relaxation

81. Action potentials:

A. travel along neurons at a set velocity

B. are only seen in neurons

C. are generated initially by action of K+ voltage gated channels

D. result from variation in Na+ and K+ membrane permeability

E. are unidirectional impulses

Correct : D. result from variation in Na+ and K+ membrane permeability

82. The Na+ K+ ATPase pump:

A. utilises ATP to pump out 2 Na+ ions for every 3 K+ ions

B. activity is altered by insulin, aldosterone and thyroid hormones

C. is only found in muscle and nervous tissue

D. is made of α, β, and δ subunits

E. ATP binds to the α subunit causing a protein configuration change

Correct : B. activity is altered by insulin, aldosterone and thyroid hormones

83. Which is TRUE?

A. active transport is the major method for transport of glucose into cells

B. facilitated diffusion utilises ATP to transport ions against their chemical or electrical gradients

C. an example of an active transporter is the K+ H+ ATPase found in the gastric mucosa

D. the H+ K+ ATPase is an example of an electrogenic pump

E. none of the above

Correct : C. an example of an active transporter is the K+ H+ ATPase found in the gastric mucosa

84. The golgi apparatus, which is TRUE?

A. is found only in secretory cells

B. vesicles containing newly synthesised proteins bind to trans side of the apparatus

C. constitutive pathway of cell secretion is responsible for further processing and storage of proteins

D. is responsible for glycorylation of proteins

E. none of the above

Correct : E. none of the above

85. With respect to protein synthesis:

A. each amino acid found in human protein has its own individual single transfer RNA

B. pre mRNA processing occurs in the cytoplasm prior to binding to ribosomes on the endoplasmic retic???

C. each gene has regulatory, promoter, coding and non coding regions which are all transcribed into pre mRNA

D. introns no recognised physiological function

E. the promoter site of a gene is the site where RNA polymerase binds

Correct : E. the promoter site of a gene is the site where RNA polymerase binds

86. Which is TRUE?

A. polymerase chain reaction may be used to repair damaged DNA

B. restriction fragment length polymorphism detects differences in DNA sequences between different individuals

C. protein encoding genes make up only 15% of the human genome

D. the only difference between DNA and RNA is the substitution of uracil for thymine

E. the haploid human genome is made up of 3 X 106 base pairs

Correct : B. restriction fragment length polymorphism detects differences in DNA sequences between different individuals

87. Action potentials in skeletal muscle:

A. travel along muscle fibres at varying rates

B. have larger retratory periods compared to nerves

C. causes uptake of Ca++ into sacroplasmic reticulum

D. results in sustained contraction of muscle fibres

E. the haploid human genome is made up of 3 X 106 base pairs

Correct : B. have larger retratory periods compared to nerves

88. Regarding membrane potential:

A. it is only found in nervous tissue

B. Na+/K+ pump does not contribute to the membrane potential

C. its magnitude does not change from tissue to tissue

D. the membrane potential is negative inside in relation to the outside

E. it is mainly caused by leaking Na+/K+ channels

Correct : D. the membrane potential is negative inside in relation to the outside

89. Gamma amino butyric acid:

A. is an excitatory mediator in the brain

B. it is formed by decarboxylation of glutamates

C. there are three different classes of GABA receptors

D. it is mostly excreted unchanged in the urine

E. is the main mediator in glutamate metabolism

Correct : B. it is formed by decarboxylation of glutamates

90. Substance P:

A. is a carbohydrate

B. is a polypeptide found in intestine and nervous tissue

C. is a beta II amino acid residue mainly found in the liver

D. it is not involved in the neuroendocrine system

E. it is a lipid

Correct : B. is a polypeptide found in intestine and nervous tissue

91. Opioid peptides:

A. are not formed from precursors

B. morphine is an example of opioid peptides

C. they form the opioid receptors in the brain

D. are mainly found in the brain and gastrointestinal

E. they are excreted unchanged almost always

Correct : D. are mainly found in the brain and gastrointestinal

92. Regarding the autonomic nervous system:

A. does not have a reflex arc like somatic nervous system

B. dopamine is the main transmitter

C. cholinergic division of the autonomic nervous system increases activity of the intestinal musculature and increases gastric secretion

D. norepinepherine is metabolised by pseudocholinesterase

E. it is not involved with visceral sensation

Correct : C. cholinergic division of the autonomic nervous system increases activity of the intestinal musculature and increases gastric secretion

93. With respect to blood volume:

A. the greater proportion is present in the arterial system

B. the pulmonary vessels contain 50%

C. the systemic capillaries and arterioles contain 7%

D. the heart contains 20%

E. the aorta contains 20%

Correct : C. the systemic capillaries and arterioles contain 7%

94. Blood pressure:

A. fluctuates in the aorta between 180 and 20mmHg

B. is approaching 0mmHg at the right atrium

C. is half in the pulmonary arteries of that in the aorta

D. is greater in large veins than the vena cava

E. drops significantly at capillary level

Correct : B. is approaching 0mmHg at the right atrium

95. With respect to blood flow:

A. during laminar flow, blood moves at greater velocity adjacent to the vessel wall

B. turbulent flow can occur in long straight vessels

C. during turbulent flow, there is less resistance to flow

D. the tendency for turbulent flow increases inversely with the velocity of blood flow

E. turbulent flow does not normally occur in the aorta

Correct : B. turbulent flow can occur in long straight vessels

96. As a percentage of total blood volume, which of the following values are CORRECT?

A. 40% is in the pulmonary circulation

B. 13% is in the systemic arteries

C. 20% is in the systemic arterioles and capillaries

D. 30% is in the veins

E. none of the above are correct

Correct : B. 13% is in the systemic arteries

97. Which is NOT correct about reflex mechanisms acting on the circulation?

A. the baroreceptors in the carotid bodies are stimulated when blood pressure increases

B. the Bainbridge reflex causes increase in heart rate

C. the Cushing reflex is a special central nervous system ischaemic response resulting from increased intracranial pressure

D. the maximum firing per change in pressure of the carotid baroreceptors occurs at a mean arterial pressure of 90mmHg

E. the glossopharyngeal nerve is involved in baroreceptor reflex system

Correct : A. the baroreceptors in the carotid bodies are stimulated when blood pressure increases

98. When the cholinergic vagal fibres to nodal tissues are stimulated:

A. the membrane becomes hyper-polarised

B. the slope of the pre-potential is decreased

C. acetylcholine decreases conductance to Ca++ via muscarinic receptors

D. acetylcholine increases the permeability of nodal tissues to K+ via muscarinic receptors

E. all of the above are true

Correct : E. all of the above are true

99. Heart rate is accelerated by:

A. decreased activity of baroreceptors in the left ventricle

B. increased activity of baroreceptors in the pulmonary circulation

C. increased intracranial pressure

D. expiration

E. increased activity of baroreceptors in the arteries

Correct : A. decreased activity of baroreceptors in the left ventricle

100. Regarding the physical characteristics of the circulation:

A. arterioles have a strong muscular wall but can close completely

B. the arterial system contains the greatest volume of blood at any given time

C. the aorta has a greater total cross sectional area than the venae cavae

D. velocity is directly proportional to the cross sectional area of the blood vessel

E. Reynold’s number represents a measure of laminar blood flow

Correct : A. arterioles have a strong muscular wall but can close completely

Quiznetik

Physiology | Set 3

1. With regard to the metabolism of carbohydrates:

2. With regard to lipid metabolism:

3. With regard to carbohydrate metabolism:

4. Which statement regarding glucagon is INCORRECT?

5. Which of the following is NOT an action of somatostatin?

6. Glucagon increases the secretion of all of the following EXCEPT:

7. Regarding the actions of glucagon, which of the following is INCORRECT?

8. Which of the following does NOT increase pancreatic polypeptide secretion?

9. Which iodinated compound is present in GREATEST amounts in the adult thyroid gland?

10. Regarding the action of glucagon on the liver, which of the following is INCORRECT?

11. Regarding the synthesis of thyroid hormones, which statement is INCORRECT?

12. Which of the following does NOT inhibit secretion of glucagon?

13. Which plasma protein has the greatest thyroxine binding capacity?

14. Which of the following does NOT increase secretion of glucagon?

15. Which plasma protein has the greatest thyroxine-binding affinity?

16. Regarding insulin, which statement is INCORRECT?

17. Which iodinated compound is present in the SMALLEST amounts in the adult thyroid gland?

18. Which of the following hormones does NOT increase the hepatic output of glucose?

19. Which thyroid hormone has the longest plasma half-life?

20. Regarding the action of insulin on adipose tissue, which of the following is INCORRECT?

21. Which of the following tissues possess FEW thyroid hormone receptors?

22. Which glucose transporter is responsible for insulin-mediated glucose uptake in striated muscle and adipose tissue?

23. Where are the receptors located by which thyroid hormones mediate most of their effects?

24. Regarding the action of insulin in skeletal muscle, which of the following is INCORRECT?

25. Which thyroid hormone possesses the GREATEST biological activity?

26. Which glucose transporter is responsible for the facilitated diffusion of glucose into pancreatic B cells?

27. Regarding the effects of thyroid hormones, which of the following does NOT occur?

28. Regarding the action of insulin on the liver, which of the following is INCORRECT?

29. Which statement regarding the thyroid gland and its hormones is INCORRECT?

30. Regarding the secretion of insulin, which statement is INCORRECT?

31. Which of the following do NOT increase TSH secretion?

32. Which of the following does NOT inhibit insulin secretion?

33. Which of the following does NOT increase intestinal calcium absorption?

34. Which of the following does NOT stimulate insulin secretion?

35. Which of the following does NOT decrease intestinal calcium absorption?

36. Regarding the insulin receptor, which statement is INCORRECT?

37. Which of the following does NOT increase plasma calcium?

38. Which of the following is NOT associated with an increase in erythropoietin secretion?

39. Which of the following does NOT increase parathyroid hormone secretion?

40. Regarding erythropoietin, which statement is INCORRECT?

41. Which statement regarding parathyroid hormone (PTH) is INCORRECT?

42. Regarding endothelins, which statement is INCORRECT?

43. Which statement regarding calcitonin is INCORRECT?

44. Regarding atrial natriuretic peptide, which statement is INCORRECT?

45. Regarding the role of vitamin D in calcium metabolism, which of the following is INCORRECT?

46. Atrial natriuretic peptide decreases formation of all of the following EXCEPT:

47. Which of the following does NOT increase aldosterone secretion?

48. Which of the following does NOT increase secretion of atrial natriuretic peptide?

49. Regarding aldosterone, which statement is INCORRECT?

50. A 15-year-old girl suffers from a malabsorption syndrome characterised by the malabsorption of fat. In which vitamin is she MOST likely to be deficient?

51. Thyroxine (T4):

52. Regarding insulin:

53. The content of chylomicrons includes:

54. Regarding calcium metabolism:

55. Regarding cellular components:

56. Na+ -K+ -ATPase is an example of a/an:

57. Which decreases Na+ -K+ -ATPase pump activity?

58. Given that a person weighs 60kg and their haematocrit is 40%, their total blood volume is:

59. What percentage of body weight is plasma?

60. ECF volume can be estimated using:

61. The number of molecules in a mole is:

62. The molecular mass of a substance is expressed in:

63. Regarding mitochondria:

64. Which volume of distribution is evaluated with which substance?

65. Which is correct?

66. For mitochondria, which is TRUE?

67. Which is TRUE?

68. For the genome, which is TRUE?

69. For transmembrane movement, which is TRUE?

70. For the Erlanger and Gasser classification, which is TRUE?

71. For the glial cells, which is TRUE?

72. For cardiac muscle, which is FALSE?

73. For neurotransmitters, which is TRUE?

74. Regarding body water, which is FALSE?

75. Chemical composition, which is TRUE?

76. Nerve fibres, which is FALSE?

77. Regarding skeletal muscle, which is FALSE?

78. More on muscles; which is TRUE?