NDM MCQ Final 2005

1

In vitro cultivation of intestinal contents from healthy humans has indicated that the predominant community of the intestinal microbiota comprises:


  facultatively anaerobic Gram negative rods, e.g., Escherichia spp.

  microaerophilic Gram negative curved rods, e.g., Helicobacter spp.

  facultatively anaerobic Gram positive cocci, e.g., Enterococcus spp.

  obligately anaerobic Gram positive rods, e.g., Clostridium spp.

  obligately anaerobic Gram negative rods, e.g., Bacteroides spp.

2

Indicate the CORRECT statement regarding the intestinal microbiota:


  commensal bacteria seldom causes infections at extra-intestinal sites.

  the gastrointestinal microbiota of humans plays an essential role in digestion and nutrition.

  antibiotic-associated diarrhoea is caused by the overgrowth of susceptible bacteria, such as Escherichia coli.

  some harmless bacteria which colonise the intestine share antigens with pathogenic bacteria and hence can act as “natural vaccines”.

  the ingestion of large numbers of probiotic bacteria, such as lactobacilli, can radically alter the composition of the intestinal microbiota of healthy people.

3

Which of the following statements about the action and effects of insulin is CORRECT?


  The binding of insulin to its receptor leads to autophosphorylation of the extracellular domains of the insulin receptor.

  Insulin enters the cell via a process of receptor-mediated endocytosis.

  Insulin causes down-regulation of pyruvate kinase.

  Insulin secretion after a meal increases the number of GLUT4 molecules on the plasma membranes of muscle cells.

  Insulin binding initiates the activation of GSK3.

4

Which of the following statements about protein breakdown is CORRECT?


  Gluconeogenesis using amino acids derived from skeletal muscle is the major source of blood glucose after 6–10 days of starvation.

  Oxidative metabolism of branched chain amino acids provides the major source of energy for the kidney.

  The first step in the catabolism of amino acids involves the formation of ammonia, catalysed by aminotransferase enzymes.

  Glycine is the only amino acid that cannot be used in gluconeogenesis.

  The sole site of cellular protein degradation is the lysosomal compartment of the cell.

5

Which of the following statements about LDL (low density lipoprotein), HDL (high density lipoprotein) and the risk of coronary heart disease (CHD) is CORRECT?


  Increasing plasma levels of LDL lower the risk of CHD.

  Increasing plasma levels of HDL lower the risk of CHD.

  The risk of CHD decreases as the ratio of LDL cholesterol to HDL cholesterol increases.

  Increasing levels of HDL cholesterol do not affect the risk for patients with a family history of CHD.

  The risk of CHD is independent of the total plasma concentration of cholesteryl esters.

6

Which of the following statements about enzymes and other proteins involved in lipid metabolism is CORRECT?


  Hepatic lipase converts LDL to HDL.

  ApoA-I activates lipoprotein lipase (LPL).

  Lipoprotein lipase is active in endothelial cells in adipose tissue and muscle.

  Acyl-CoA cholesterol acyl transferase (ACAT) is a plasma enzyme.

  Acetyl-CoA is a substrate in the reaction catalysed by ACAT.

7

Which of the following statements about intracellular cholesterol metabolism is CORRECT?


  Free cholesterol is released when LDL binds the LDL receptor (LDLR).

  β-hydroxy-β-methylglutaryl-CoA reductase (HMG-CoA reductase) catalyses the rate limiting step in cholesterol synthesis.

  The LDL receptor is up-regulated when intracellular cholesterol levels increase.

  The action of glucagon increases the rate of cholesterol synthesis.

  Esterification of cholesterol decreases as the intracellular cholesterol concentration increases.

8

Which of the following statements about ketone bodies in fasting is CORRECT?


  The synthesis of ketone bodies spares liver glycogen.

  Ketone bodies are synthesized in adipose tissue from fat breakdown.

  Beta hydroxybutyrate is formed by reduction of acetoacetate.

  Ketone bodies are important for energy supply to the red cells after three weeks of starvation.

  The synthesis of ketone bodies requires one ATP for each acetyl-CoA entering the pathway.

9

Which of the following statements about insulin is CORRECT?


  Mature insulin has one interchain and two intrachain disulphide bonds.

  Low blood glucose triggers the proteolysis of proinsulin in the pancreas to release the C peptide.

  Preproinsulin is the stored form of insulin.

  Insulin activates glycogen phosphorylase.

  Insulin enters the blood from the beta cells of the pancreatic islets via the lymphatic system.

11

The major source of ATP production during a 30 second "all-out", high intensity exercise bout is:


  creatine phosphate breakdown.

  intramuscular ATP stores.

  lactate oxidation.

  anaerobic glycolysis of muscle glycogen.

  glucose oxidation.

12

Regular physical exercise can enhance insulin action and may benefit individuals with type 2 diabetes. A crucial skeletal muscle adaptation contributing to improved insulin action is:


  increased muscle glycogen levels.

  lowered intramuscular triglyceride.

  enhanced GLUT4 expression.

  reduced mitochondrial density.

  decreased hexokinase activity.

13

In pathology assays for a specific enzyme in blood, released from damaged tissue, the level measured is NOT expected to correlate with which one of the following?


  The degree of cellular damage.

  The half life or rate of removal of the enzyme from serum.

  The time that has elapsed since cellular damage occurred.

  The presence in the blood of cellular enzymes from other tissues.

  The level of the enzyme in the damaged cell.

14

Elevation of blood levels of which enzyme is most specific as an indicator of hepatocyte damage?


  Aspartate aminotransferase (AST).

  Creatine phosphokinase (CK).

  Lactate dehydrogenase (LD).

  Alanine aminotransferase (ALT).

  Gamma glutamyltransferase (GGT).

16

Regarding leptin which of the following statements in NOT CORRECT?


  Leptin is a peptide hormone discovered in 1994.

  Leptin inhibits food intake.

  Leptin is made in the hypothalamus and released after meals.

  A deficiency of leptin results in severe obesity.

  Leptin suppresses production of NPY in the hypothalamus.

17

Regarding potential complications of obesity which of the following in NOT CORRECT?


  Hypothyroidism.

  Polycystic ovarian syndrome.

  Obstructive Sleep Apnoea.

  Breast cancer.

  Type 2 diabetes.

19

With regard to the enteric nervous system indicate the one CORRECT statement below.


  The ganglia of the enteric nervous system consist of parasympathetic post-ganglionic neurons.

  The enteric nervous system plays an essential role in whole body fluid and electrolyte homeostasis.

  You could survive without an enteric nervous system.

  The major enteric neurotransmitters are glutamate, GABA and aspartate.

  The enteric nervous system is not present in the esophagus.

20

With regard to digestive system endocrine functions, indicate the one CORRECT statement below.


  CCK is the major hormone that controls bicarbonate secretion from the pancreas.

  The endocrine hormones of the stomach are located in submucosal glands.

  Gastric acid secretion is controlled positively by gastrin and negatively by somatostatin.

  Enteric neurons and gastrin have opposite effects on the acid-secreting parietal cells.

  CCK is released from the gallbladder.

21

In order to create a muscle flap for reconstructive surgery, a plastic surgeon dissects out the rectus abdominus muscle and identifies the posterior compartment of the rectus sheath. Above the level of the arcuate line the posterior layer of the rectus sheath is:


  absent.

  comprised of the aponeuroses of all 3 layers of the anterior abdominal wall.

  comprised of the aponeurosis of external oblique and the anterior leaf of the internal oblique aponeurosis.

  comprised of the aponeurosis of transverses abdominis and the posterior leaf of the internal oblique aponeurosis.

  comprised of thoracolumbar fascia.

22

Emergency surgery is performed on a night club patron who has been stabbed and a large laceration in the liver is identified. In order to stop the bleeding the portal vein and hepatic artery can be clamped proximal to the porta hepatis where they:


  pass anterior to the first part of the duodenum and head of pancreas.

  pass in the free edge of the lesser omentum.

  are retroperitoneal.

  are in contact with the anterior abdominal wall.

  are in contact with the posterior abdominal wall.

23

In portal hypertension alternative pathways for blood flow result in engorgement of anastomotic channels at sites of porto-systemic overlap. Which one of the following is NOT a site of porto-systemic anastomosis?


  The lower oesophagus.

  The anal canal.

  The porta hepatic.

  The anterior abdominal wall.

  The retroperitoneal tissues.

24

A patient has infarction of the jejunum and ileum due to an embolus arising from the left atrium of the heart. The vessel most likely occluded by this embolus is the:


  coeliac artery.

  superior mesenteric artery.

  inferior mesenteric artery.

  aorta below the level of the renal arteries.

  portal vein.

25

A 32 year old man with severe left sided abdominal pain is suspected of having a left ureteric calculus (stone lodged in the left ureter). On plain abdominal X-ray the course of the left ureter can be traced along:


  the lateral border of psoas.

  the lateral margins of the lumbar vertebral bodies.

  the tips of the lumbar transverse processes.

  the tip of the 12th rib.

  the lateral border of quadratus lumborum.

26

A young motorcyclist sustains a fracture of his left 10th and 11th ribs in a fall from his bike. The abdominal viscus most likely to be injured is the:


  liver.

  gallbladder.

  stomach.

  spleen.

  left kidney.

27

Which type of large intestinal polyp is associated with an increased risk of developing colorectal carcinoma?


  Inflammatory polyp.

  Hamartomatous polyp.

  Hyperplastic polyp.

  Adenomatous polyp.

  Sessile polyp.

28

Adenocarcinoma of the large bowel:


  does not invade tissue.

  does not obstruct the lumen.

  is not associated with ulceration or bleeding.

  does not spread to other organs.

  may be staged using the Duke's staging system.

29

Indicate the one CORRECT statement about Coeliac disease.


  Coeliac disease subjects have an antibody to gluten in the diet.

  Coeliac disease is a disease affecting the large intestine.

  Coeliac disease is an example of a neuromuscular disorder.

  Coeliac disease is associated with skip lesions in the bowel.

  Coeliac disease resolves with antibiotic treatment.

30

Which of the following statements regarding arachidonic acid metabolism is CORRECT?


  Leukotriene B4 (LTB4) is a potent constrictor of airway smooth muscle.

  An increase in the synthesis of prostaglandin E2 in the hypothalamus causes fever.

  Inhibition of lipoxygenase in the stomach, and therefore decreased synthesis of prostacyclin (PGI2) and PGE2, may lead to irritation and ulceration.

  Phospholipase converts arachidonic acid to the unstable intermediate prostaglandin G2.

  After release from phospholipid stores arachidonic acid is metabolised to prostaglandins predominantly in the liver.

31

Antoine Lavoisier is considered to have founded the study of modern chemistry and quantitative nutrition. His pioneering work led to which one of the following conclusions?


  Life is a process of combustion.

  Life requires many compounds based on carbon (i.e. organic chemicals).

  A typical adult human requires and expends 10MJ of energy per day.

  Asphyxiation follows from lack of oxygen.

  Some bacteria can live without oxygen, unlike animals.

32

Given that four (4) of the following terms are synonyms, indicate the one term that is not comparable to the others.


  Specific Dynamic Effect.

  Basal metabolic rate.

  Postprandial thermogenesis.

  Heat increment of feeding.

  Diet induced thermogenesis.

33

Given that the aim is to keep a stable weight, or to permit normal growth for a child, which one of the following applies to a diet in terms of energy per kilogram?


  An obese person needs more than a normal person.

  A woman needs more than a man.

  A 60 year old needs more than a 40 year old.

  A diabetic needs more than a non-diabetic.

  A baby needs more than an adult.

34

You have been presented with some of the statistics and conclusions from Batch and Baur who published a paper about childhood obesity in the Medical Journal of Australia in 2005. According to this paper which one of the following is NOT a correct summary of best evidence (or practice) about childhood obesity in Australia?


  Rates of obesity have increased significantly in Australia from 1985 to 1995, with the prevalence of overweight doubling and obesity trebling.

  Body mass index (related to reference standards for age and sex) is recommended as a practical measure of overweight and obesity in children, and is used in monitoring individual progress in clinical practice.

  Obesity in childhood and adolescence may be associated with a range of medical and psychological complications, and can predispose individuals to serious health problems in adult life, including type 2 diabetes, hypertension, dyslipidaemia and non-alcoholic steatohepatitis.

  Obesity interventions based on leaving a child at home are rarely successful and better outcomes generally result from removing a child for a term of clinical treatment.

  20% to 25% of children and adolescents are overweight or obese, and 4.9% of boys and 5.4% of girls are obese.

35

Select the one statement about leptin that is NOT CORRECT.


  Leptin is a peptide cytokine produced by adipocytes.

  Leptin signals the amount of body fat to the hypothalamus.

  Leptin normally stimulates increased energy expenditure thereby helping to stabilise long term body weight.

  Leptin is commonly at relatively low levels in obese humans.

  Leptin in mice is coded for by the Ob gene.

36

Food pyramids are a convenient way of making dietary recommendations to patients. The USDA food pyramid of 1992 was widely used in the world until replaced by “MyPyramid” in 2005. In the following list indicate the only feature that is a common recommendation between the two pyramids.


  Foods rich in fibre.

  Foods rich in unsaturated fat.

  Foods rich in omega-3 fats.

  Regular exercise.

  Alcohol consumption in moderation.

37

The glycaemic index is:


  a ranking of dietary proteins based on their content of essential amino acids.

  a ranking of dietary proteins based on their ability to support gluconeogenesis.

  a ranking of dietary carbohydrates based on their effect on blood glucose.

  an historical measure of blood glucose, replaced by using mM (milliMolar).

  an index of sweetness in foods.

38

Indicate the one CORRECT statement about free fatty acids (FFA), also known as non-esterified fatty acids.


  FFA is found in high concentration within the lipid droplet of adipocytes.

  FFA is released from liver in response to adrenaline.

  FFA in blood plasma is distributed between a number of carriers and most concentrated within VLDL particles.

  FFA in blood plasma is mostly carried bound to serum albumin.

  FFA is also characterised as neutral lipid.

39

Indicate the one CORRECT statement about dietary protein.


  Kjeldahl Nitrogen Analysis is a technique applicable to the determination of protein in food.

  100 grams of a typical dietary protein contains 6grams of nitrogen.

  The most significant nitrogen rich excretion product in humans is uric acid.

  Based on Australian recommended intake a typical 70kg male would be expected to remain in nitrogen balance on a daily diet with 40 grams of good quality protein.

  Soy protein is among the least nutritious sources of protein in common foods as judged by Net Protein Utilsation (a value that gives an index of nutritional value).

40

The Gluconeogenic pathway:


  Is active in muscle recovering from anaerobic lactate production.

  Requires the input of 4ATP and 2NADH for each molecule of glucose made.

  Has two steps that are different to glycolysis (bypass reactions).

  Can use oxaloacetate, pyruvate or acetyl-CoA as a source of carbons for glucose.

  Can use ketones in prolonged fasting as a source of carbons for glucose.

41

In mitochondria the gamma-subunit of ATP synthase (respiratory complex V) has the function of:


  displacing ATP from beta subunits by mechanical action as the gamma subunit rotates.

  catalysing the condensation of ADP with phosphate to ATP.

  ensuring that protons do not leak through the complex of subunits.

  binding protons at the intermembrane space in mitochondria then flipping to release protons in the mitochondrial matrix.

  making a dimer with alpha subunits and forming a cluster of three dimers (α3γ3) as the functional unit for ATP synthesis.

42

Which one of the following is a CORRECT characteristic common to all cytochrome P450 enzymes involved in detoxification?


  An iron-sulphur complex in which the iron alternates between Fe2+ and Fe3+ as electrons are donated to oxygen.

  An active site which is specific for a unique substrate that becomes hydroxylated, or otherwise oxygenated.

  A hydrophobic protein “foot” that anchors the P450 to the inner mitochondrial membrane.

  An absorbance maximum of 450 nm when oxidised to the Fe3+ state.

  Expression at higher levels when substrates are persistently present i.e cytochrome P450s are inducible.

43

The liver component designated CYP 2E1 is involved in which one of the following ways with drug/metabolite metabolism?


  CYP 2E1 initiates smooth endoplasmic reticulum proliferation.

  CYP 2E1 is also known as aromatase and modifies steroid hormones.

  CYP 2E1 is active in the microsomal ethanol oxidising system.

  CYP 2E1 has codeine as a substrate and poor metabolisers of codeine lack this activity.

  CYP 2E1 is induced to high levels by as little as a picogram of dioxin.

44

The podocyte is a key cell in the functioning of the renal corpuscle. Which of the following correctly describes the location and function of podocytes?


  Found between the base of the loops of the glomerular capillaries to help stabilize the glomerular structure.

  Located on the outer surface of the glomerular capillaries and provides part of the filtration barrier in the form of the slit membrane.

  A sensory structure that forms part of the wall of the distal convoluted tubule and found adhering to the renal corpuscle between the afferent and efferent arterioles.

  Squamous cells forming the outer surface of the renal corpuscle around Bowman's space.

  Modified smooth muscle cells in the wall of the afferent and efferent arterioles that release the enzyme renin.

45

After an ultrafiltrate is formed in the renal corpuscle, it is further modified as it flows through a tubular system before leaving the kidney in the ureter. Which part of the tubular system includes a region made up of thin, squamous cells?


  Proximal tubule.

  Distal Tubule.

  Loop of Henle.

  Macula densa.

  Collecting duct.

46

Anaemia due to iron deficiency is typically associated with four of the five conditions listed. Which one of the following is not an indicator of anaemia due to iron deficiency?


  A subnormal serum ferritin level.

  Microcytosis.

  Decreased haem production.

  A subnormal serum transferrin level.

  A subnormal serum iron level.

47

Beta thalassaemia minor is typically associated with which one of the following?


  Mutations in both beta globin genes.

  An abnormal globin amino acid sequence.

  Transfusion-dependent anaemia.

  A decreased percentage of haemoglobin A2 in red cells.

  A subnormal mean red cell volume.

48

Which one of the following is NOT CORRECT with respect to the binding of oxygen to haemoglobin? Oxygen binding to normal haemoglobin:


  decreases with a rise in red cell diphosphoglycerate (also called 2,3-bisphosphoglycerate).

  requires haem iron to be in the ferric state.

  increases as red cell pH rises.

  is related to oxygen partial pressure in a non-linear manner.

  increases during red cell transit through alveolar capillaries.

49

Indicate the one statement about smooth muscle that is CORRECT.


  Smooth muscle cells contain actin and myosin arranged in regular sarcomeres.

  Multi-unit smooth muscle shows myogenic activity and behaves as a syncitium.

  The resting membrane potential of smooth muscle cells shows great constancy, unlike other types.

  Smooth muscle of the stomach wall is able to increase its length significantly without altering its tone (i.e. shows plasticity).

  In peristaltic contractions concerned with the propulsion of food the circular smooth muscle contracts first and, halfway through its contraction, the longitudinal muscle begins to contract.

50

In radiological imaging of the abdomen which one of the following is CORRECT?


  Intravascular contrast agents contain calcium atoms to increase absorption of X-rays.

  Radioisotope scanning relies on detection of electromagnetic radiation using a gamma camera.

  Ultrasound relies on absorption of the ultrasound beam to generate images.

  The Doppler effect is used to measure the density of tissue.

  Magnetic resonance can be used in patients with cardiac pacemakers because it does not use ionizing radiation.

51

In radiographic (X-ray) imaging of the abdomen which of the following does NOT influence the amount of absorption of X-rays by the body:


  the type of Xray film.

  the use of intravascular contrast agents.

  thickness of tissue.

  density of tissue.

  atomic number of tissue.

52

In regard to the blood supply of the liver which one of the following is CORRECT?


  Contrast agents administered in a forearm vein will reach the hepatic artery after they reach the portal vein.

  The portal vein supplies about 25% of the volume of blood flow to the liver.

  The portal vein receives blood from the spleen.

  The hepatic artery normally arises from the superior mesenteric artery.

  There are two main hepatic veins that drain into the inferior vena cava.

53

Which of the following statements regarding full and partial agonists is always CORRECT?


  Full agonists are more effective therapies than partial agonists.

  Full agonists must be given at lower doses than partial agonists.

  Partial agonists act more slowly than full agonists.

  Partial agonists elicit a smaller maximal effect than full agonists.

  Partial agonists occupy fewer receptors than full agonists.

54

Which of the following statements is CORRECT?


  Competitive antagonists do not bind to the same receptors as the agonists that they antagonise.

  Agonists are unable to mediate any effect in the presence of a competitive antagonist.

  Competitive antagonists are less selective in effect than non-competitive antagonists.

  Weak partial agonists can also act as competitive antagonists.

  Competitive antagonists interfere with agonist signalling at a site distal to the receptor.

55

Which of the following types of drugs could selectively inhibit the increase in cardiac contractile force in response to adrenaline but not in response to histamine?


  A competitive antagonist of the histamine H2 receptor.

  A competitive antagonist of the β1-adrenoceptor.

  An agonist that mediates a decrease in contractile force by activating adenosine receptors.

  An inhibitor of the opening of cardiac L-type calcium channels.

  An inhibitor of the release of intracellular calcium stores.

57

Which one of the following statements concerning hepatic sinusoidal endothelial cells is CORRECT?


  Hepatic sinusoidal endothelial cells contain fenestrae covered by a thin membrane.

  Hepatic sinusoidal endothelial cells contain clusters of fenestrae forming “sieve plates”.

  Hepatic sinusoidal endothelial cells have no boundary with the Space of Disse.

  Hepatic sinusoidal endothelial cells rest on a basement membrane.

  Hepatic sinusoidal endothelial cells cannot promote hepatic stellate cell activation in response to injury.

58

Which one of the following statements concerning Kupffer cells is CORRECT?


  Kupffer cells have cytoplasmic extensions called macropodia.

  Kupffer cells lack phagocytic activity.

  Kupffer cells may be found within portal tracts in alcoholic hepatitis.

  Kupffer cells stretch across the sinusoidal lumen.

  Kupffer cells lack cyclo-oxygenase activity and do not release prostaglandins when activated.

59

Which one of the following statements concerning hepatic regeneration is CORRECT?


  Following hepatectomy, the hepatocytes are capable of replacing at least twice their mass by proliferation.

  Following extensive liver injury, regeneration is initiated by the division of biliary epithelial cells.

  Hepatic regeneration results in decreased numbers of binucleate hepatocytes.

  Hepatic regeneration results in liver cell plates that are one cell-thick.

  Under normal circumstances, most hepatocytes are in the S phase of the cell cycle.

60

Which one of the following statements concerning haemochromatosis is CORRECT?


  Haemochromatosis may result in an emphysema.

  Haemochromatosis decreases the risk of diabetes by lowering blood glucose.

  Haemochromatosis may be a secondary complication of primary adrenal cancer.

  Haemochromatosis is more likely to occur in females.

  Haemochromatosis is associated with an increased risk of hepatocellular carcinoma.

61

Which one of the following statements concerning the features of fulminant hepatitis is CORRECT?


  Fulminant hepatitis is associated with normal levels of bilirubin.

  Fulminant hepatitis is associated with a normal bleeding profile.

  Fulminant hepatitis can be caused by hepatitis B virus infection.

  Fulminant hepatitis can be associated with hepatomegaly.

  Fulminant hepatitis can be associated with chronic renal failure.

62

The nephrotic syndrome is characterized by oedema and:


  heavy haematuria.

  heavy proteinuria.

  hypertension.

  renal calculi (stones).

  acidosis.

63

Acute renal failure may have renal causes or be due to extra-renal causes. Of the renal causes of acute renal failure, the most common is:


  immune complex mediated glomerulonephritis.

  renal infections such as renal tuberculosis.

  long standing hypertension.

  acute tubular necrosis following renal ischaemia.

  diabetes mellitus.

64

Diabetes mellitus causes several forms of renal damage, including:


  glomerulosclerosis.

  deposition of crystalline sugars in renal tissue.

  immune complex glomerulonephritis.

  increased risk of renal tumours.

  increased viscosity of urine.

65

Administration of the competitive β-adrenoceptor antagonist propranolol to a patient can sometimes cause an decrease in heart rate, but sometimes does not. When would propranolol cause a decrease in heart rate? A) When the sympathetic tone to the heart is high because of acutely lowered blood pressure. B) When both parasympathetic and sympathetic tone to the heart are elevated. C) When the patient is being treated with a stable β-adrenoceptor agonist. D) When the parasympathetic tone to the heart is high because of acutely elevated blood pressure.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

66

An initial drug loading dose is likely to be desirable when: A) the drug has rapid distribution to its site of action. B) the drug has a narrow therapeutic window. C) the drug is eliminated with zero-order kinetics. D) the drug has a long half life.


  If only A, B and C are correct.

  If only A, B and C are correct.

  If only A and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only B and D are correct.

  If only D is correct.

  If only D is correct.

  If all are correct.

  If all are correct.


68 Consider an antagonist that is effective at reducing the response to an agonist, but cannot eliminate the response even at very high doses. Which of the following conditions is sufficient to explain the failure of the antagonist to completely prevent responses to the agonist? A) The antagonist is a partial agonist and the agonist is a full agonist. B) The antagonist is non-competitive and the agonist stimulates two different pathways. C) The antagonist is competitive and the agonist is a partial agonist. D) The antagonist is competitive and the agonist activates two different receptor types.

69

Which of the following properties will contribute to a drug being effective at low doses? A) High efficacy. B) High bioavailability. C) High affinity. D) Rapid dissociation from receptors.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

70

Drug metabolism in the liver may: A) decrease the activity of a drug. B) be altered by the patient’s diet. C) make a drug more water soluble. D) increase the activity of a drug.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

71

Which of the following statements related to gastrin is/are CORRECT? A) Gastrin increases gastro-oesophagal sphincter tone. B) Gastrin release is stimulated by protein breakdown products. C) Gastrin is a competitive inhibitor of cholecystokinin. D) Gastrin relaxes the pylorus.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

72

Which of the following statements related to acid secretion by the gastric gland is/are CORRECT? A) Acid is secreted by the peptic cell. B) Acid secretion is increased by protein digestion products in the duodenum. C) The effect on acid secretion of histamine and gastrin is additive. D) Acid secretion is increased by protein digestion products in the antrum.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

73

Which of the following statements related to peptic ulceration is/are CORRECT? A) Histamine increases acid secretion by a direct effect on the peptic cell. B) Aspiration of gastric juice will lead to a metabolic acidosis. C) Most peptic ulcers can be cured by antacid therapy. D) Aspiration of gastric juice will lead to hypokalaemia.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

74

Which of the following statements related to peptic ulceration is/are CORRECT? A) Most acid is secreted from the body of the stomach. B) Aspiration of gastric juice will lead to a metabolic alkalosis. C) Acid secretion can be reduced by antrectomy. D) Bicarbonate is secreted by gastric mucosal cells.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

75

Which of the following statements related to digestion of food is/are CORRECT? A) α amylase breaks starches down to disaccharides. B) Trypsinogen is activated by trypsin. C) Disaccharidases are secreted into the intestinal lumen. D) Trypsinogen is activated by enterokinase.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

76

Which of the following statements related to the pancreas and its secretion is/are CORRECT? A) α amylase is secreted from α cells of the pancreas. B) Glycogen is secreted by alpha (α) cells of the pancreas. C) Trypsinogen is activated by a high pH. D) Pancreatic acinar cell secretions are stimulated by vagal activity.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

77

Which of the following statements related to the pancreas and its secretion is/are CORRECT? A) Limit dextrins are formed from starch by α amylase. B) Secretion of bicarbonate is stimulated by secretin. C) α amylase breaks down 1-4 glucosidic linkage. D) Trypsin is an endopeptidase.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

78

Which of the following statements related to digestion of food is/are CORRECT? A) α dextrinase breaks 1-6 glucosidic bonds. B) Trypsinogen is activated by a high pH. C) Pepsin is an endopeptidase. D) Trypsinogen is activated in the pancreas.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

79

Which of the following statements related to the causation of diarrhoea is/are CORRECT? A) Increased intestinal cell cytosolic Ca++ causes diarrhoea. B) Excess histamine may cause diarrhoea. C) Increased cyclic AMP in intestinal mucosal cells may cause diarrhoea. D) Decreased levels of cyclic AMP in intestinal mucosal cells may cause diarrhoea.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

80

Which of the following statements related to malabsorption is/are CORRECT? A) Iron malabsorption is the most common cause of iron deficiency. B) Parathyroid hormone directly stimulates intestinal calcium absorption. C) Approximately 40% of iron in the diet is absorbed in a normal person. D) Calcium malabsorption is common in renal disease.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

81

Which of the following statements related to liver metabolic functions is/are CORRECT? A) Globulins are synthesised by the liver. B) Aldosterone is metabolized by the liver. C) The liver synthesises glucose from fatty acid metabolic products (Acetyl Co A). D) Glycogen is broken down by the liver.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

82

Which of the following statements related to liver metabolic functions is/are CORRECT? A) Steroid hormones are broken down by the liver. B) The liver synthesizes glucose from proteins. C) Cytochrome P450 is an active catabolic system of the liver. D) The liver cannot synthesize glucose from acetyl CoA.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

83

All of the following statements related to abnormal liver function and bilirubin are correct except for: A) conjugation of bilirubin is defective in premature infants. B) the presence of unconjugated bilirubin in plasma helps to distinguish hepato cellular from obstructive jaundice. C) unconjugated bilirubin is converted to a soluble form of bilirubin by ultra violet light. D) failure of conjugation of bilirubin is the primary defect leading to jaundice in hepato cellular disease.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

84

Which of the following statements related to acute jaundice and liver is/are CORRECT? A) Bruising and/or bleeding tendency occurs in both obstructive and hepato cellular jaundice. B) Albumin synthesis is impaired in acute hepato cellular jaundice. C) Vitamin K administration parenterally corrects the bleeding associated with obstructive jaundice. D) Oedema due to a low plasma albumin is common in acute hepato cellular jaundice.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

85

Which of the following statements related to acute jaundice and liver is/are CORRECT? A) Bruising and bleeding occur with all types of jaundice. B) In hepato cellular jaundice bilirubin in plasma is conjugated. C) In haemolytic jaundice bilirubin in plasma is principally unconjugated. D) In obstructive jaundice bilirubin in plasma is conjugated.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

86

Which of the following statements related to the glomerulus and glomerular filtration is/are CORRECT? A) Glomerular capillary pressure is about 70-80 mmHg. B) Oncotic pressure in afferent arteriolar blood is about 25-30 mmHg. C) Net glomerular filtration pressure is about 50-60 mmHg. D) GFR is maintained relatively constant despite blood pressure fluctuations.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

87

Which of the following statements related to the proximal tubule is/are CORRECT? A) Weak acids are actively secreted by the proximal tubule. B) Weak bases are actively reabsorbed by the proximal tubule. C) Weak bases are actively secreted by the proximal tubule. D) Weak acids are actively reabsorbed by the proximal tubule.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

88

Which of the following statements related to the collecting tubule and/or duct is/are CORRECT? A) Low plasma pH causes increased K+ excretion. B) HCO3- in lumen of the collecting tubule increases H+ excretion by the kidney. C) Aldosterone decreases H+ secretion by the collecting tubule. D) HCO3- in lumen increases H+ secretion in the collecting tubule.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

89

Which of the following statements related to the loop of Henle is/are CORRECT? A) ADH increases reabsorptive capacity of the thick ascending limb of the loop of Henle. B) If the loop of Henle is not functioning the kidney cannot concentrate urine. C) Osmolality at end of the loop of Henle is about 100 mosmol/l. D) If the loop of Henle is not functioning the kidney cannot dilute urine.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

90

Which of the following statements related to the juxtaglomerular apparatus (JGA) or the cortical diluting segment is/are CORRECT? A) High NaCl at macula densa → increased renin release. B) Efferent arteriole is more sensitive to circulating angiotensin II than the afferent arteriole. C) Angiotensin II mediates TG feedback. D) Renin is present predominantly in the afferent arteriole.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

91

Which of the following statements related to the renin angiotensin aldosterone system is/are CORRECT? A) Aldosterone increases K+ secretion. B) A high NaCl at the macula densa causes afferent arteriole constriction. C) A high plasma K+ increases aldosterone release from the adrenal. D) A low NaCl at the macula densa causes afferent arteriole dilatation.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

92

Which of the following statements related to acid base is/are CORRECT? A) Free H+ in the urine are a major mode of excretion of an acid load. B) NH4+ in the urine contributes to titratable acidity. C) HPO42- in the urine contributes to titratable acidity. D) More H+ are secreted by the proximal than by the distal nephron.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

93

Which of the following statements related to acid base is/are CORRECT? A) HCO3- loss in the urine corrects metabolic alkalosis. B) Aldosterone causes an alkalosis. C) H+ K+ ATPase causes H+ secretion in the collecting tubule. D) Volume depletion prevents correction of alkalosis.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

94

Which of the following statements related to water balance and urine concentration is/are CORRECT? A) Vasopressin increases collecting duct permeability to water. B) Loop of Henle is essential for urine concentration. C) Vasopressin increases K+ permeability in the collecting tubule. D) Loop of Henle is essential for urine dilution.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

95

Which of the following statements related to calcium and phosphate is/are CORRECT? A) Calcium absorption in the loop of Henle and distal nephron is increased by parathyroid hormone. B) Plasma ionized calcium levels controls parathyroid hormone secretion. C) Parathyroid hormone decreases proximal tubule Na+ reabsorption. D) Administration of parathyroid hormone causes calcium to be lost in the urine.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

96

Which of the following statements related to diuretics is/are CORRECT? A) Hypokalaemic alkalosis is a common side effect of diuretic therapy. B) Hyperkalaemic alkalosis may occur with diuretic therapy. C) Hyperkalaemic acidosis may occur with diuretic therapy. D) Amiloride prevents all biochemical adverse effects of thiazide diuretics.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

97

Which of the following statements related to proteinuria is/are CORRECT? A) In established oedema due to hypoalbuminaemia plasma volume measured by albumin space may be normal or increased. B) Total body sodium is the important determinant of plasma volume. C) Urinary albumin excretion in normal people is < 30 mg/day. D) A person with pitting oedema up to their knees and a serum of Na+ of 125 mmols/l will be depleted of Na+.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

98

Which of the following statements related to hypotension and acute renal failure is/are CORRECT? A) A person with acute tubular necrosis usually has a urine output < 400 ml/day. B) Acidosis is common in acute renal failure. C) A urine sodium > 60 mmol/litre in an oliguric patient suggests that the process is not immediately reversible. D) Hypokalaemia is common in acute renal failure.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

99

Which of the following statements related to hypotension and acute renal failure is/are CORRECT? A) A urine sodium > 60 mmol/litre in a hypotensive patient suggests that acute tubular necrosis has occurred. B) A urine osmolality > 450 mosmol in an oliguric patient suggests that acute tubular necrosis has occurred. C) The function of the loop of Henle is usually the 1st segment impaired when renal failure follows hypotension. D) A person with acute tubular necrosis usually has polyuria.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.

100

Which of the following statements related to chronic renal failure is/are CORRECT? A) Plasma calcium is below the normal range early in the course of chronic renal failure. B) pH is usually normal early in the course of chronic renal failure. C) pH is usually below the normal range early in the course of chronic renal failure. D) Plasma bicarbonate is usually below the normal range in patients with chronic renal failure.


  If only A, B and C are correct.

  If only A and C are correct.

  If only B and D are correct.

  If only D is correct.

  If all are correct.