1) Which of the following regarding digestion of proteins are correct, except: a) A. Pepsinogen is activated by autoactivation (pH-2)or autocatalysis b) B. The major products or protein hydrolysis are large petides and some free amino acids c) C. Most of the digested proteins are absorbed in the intestine in the form of polypeptides d) D. Trypsin and chymotrypsin are secreted by the pancreas as inactive zymogens e) E. Enterokinase activates pancreatic trypsinogen 2) Rennin acts on casein of milk in infants in presence of: a) A. Mg++  b) B. Zn++ c) C. Co++ d) D. Ca++ e) E. Mn++ 3) Pepsin contains large amounts of which of the following amino acid: a) A. Aromatic amino acids b) B. Acidic amino acids c) C. Basic amino acids d) D. Sulphur containing amino acids e) E. Neutral amino acids 4) D-amino acids are absorbed by: a) A. Active transport b) B. In presence of a „carrier‟ molecule c) C. In presence of sodium ions d) D. Passive diffusion e) E. None of the above 5) Chymotrypsin hydrolyses the peptide linkages containing: a) A. Phenyl alanine and tyrosine b) B. Phenyl alanine and lysine c) C. Tyrosine and lysine d) D. Tyrosine and leucine e) E. Phenylalanine and leucine 6) Quantitatively the most important enzyme involved in formation of NH3 from aminoacids in humans is: a) A. L-amino acid oxidase b) B. Serine dehydratase c) C. Glutamate dehydrogenase d) D. Histidase e) E. Desulfhydrase 7) The two nitrogen atoms in urea arise from: a) A. Ammonia and glutamine b) B. Glutamine and aspartic acid c) C. Glutamine and glutamic acid d) D. Ammonia and aspartic acid e) E. Glutamine and alanine 8) Ochronosis is a feature of a) A. Phenyl ketonuria b) B. Hereditary tyrosinaemia c) C. Albinism d) D. Hypervitaminosis D e) E. Alkaptonuria 9) Which of the following substance is responsible for GI disturbances and respiratorydistress seen in “carcinoid syndrome”? a) A. Tryptamine b) B. 5-OH tryptamine c) C. Tyramine d) D. Histamine e) E. GABA 10) A product of the series of reactions that converts carbamoyl-(P) to urea is: a) A. Arginine b) B. Citrulline c) C. Fumarate d) D. Aspartate e) E. Adenosine triphosphate 11) Ornithine has all of the following properties except: a) A. It is an intermediate of urea cycle b) B. It is not found in proteins c) C. It is glucogenic d) D. It can be formed from arginine e) E. It is a mono-amino mono-carboxylic acid 12) Epinephrine is formed from norepinephrine by: a) A. Hydroxylation b) B. Oxidative deamination c) C. Decarboxylation d) D. N-methylation e) E. O-methylation 13) The rate limiting step in the biosynthetic pathway of catecholamines is: a) A. The hydroxylation of phenylalanine b) B. The hydroxylation of tyrosine c) C. The reduction of biopterine d) D. The formation of dopamine e) E. None of the above 14) Which of the following compounds serve as a primary link between the TCA cycle andthe urea cycle? a) A. Malate  b) B. Citrate c) C. Oxaloacetate d) D. Fumarate e) E. Succinate 15) Serine can be a percussor of each of the following, except: a) A. Cysteine b) B. Methionine c) C. Ethanolamine d) D. Glycine e) E. Choline 16) Homocystinuria is an inherited disorder characterised by: a) A. Mental retardation b) B. Frequent renal stones c) C. Aortic aneurysm d) D. Ectopia lentis e) E. Paralysis of limbs 17) . All are true about phenylketonuria, except: a) A. Deficiency of phenylalanine hydroxylase b) B. Mental retardation c) C. Increased urinary excretion of p-OH phenyl pyruvicacid d) D. Decrease serotonin formation e) E. Increase serum phenyl alanine 18) The rate of excretion of certain substances in 24-hr sample of urine can be used toestimate the rate of muscle protein loss. Which of the following substances falls into thiscategory? a) A. Ammonia b) B. Urea c) C. Uric acid d) D. 3-Methyl histidine e) E. Ergothioneine 19) Degradation and excretion of biogenic amines involve all of the following reactions,except: a) A. Conjugation to asparagines b) B. Methylation c) C. Conjugation to sulphates d) D. Conjugation to glucuronic acid e) E. All of the above 20) Tryptophan is best described by which of the following statement? a) A. It produces thyroid hormones b) B. Is a precursor for melanin c) C. It is a precursor of the pineal hormone melatonin d) D. It produces catecholamines e) E. It is glucogenic only 21) Which of the following amino acids are required for synthesis of creatine? a) A. Arginine, Asp, 'active' methionine b) B. Arginine, glycine 'active' methionine c) C. Arginine, lysine, methionine d) D. Glycine, Asp, ornithine e) E. Arginine, glutamic acid, 'active' methionine 22) Deficiency of which of the following vitamins cause creatinuria? a) A. Vitamin A  b) B. Vitamin K c) C. Vitamin E d) D. Vitamin D e) E. Vitamin B6 23) Which of the following enzyme catalyses reactions in the biosynthesis of bothcatecholamines and 5-OH tryptamine(serotonin)? a) A. Tryptophan hydroxylase b) B. Dopamine- -hydroxylase c) C. Phenyl ethanolamine N-methyl transferase d) D. Tyrosine hydroxylase e) E. Aromatic amino acid decarboxylase 24) The following statements regarding creatinine are correct except: a) A. Blood levels of creatinine is a good indicator of kidney function b) B. Although 24-hr excretion rate is very constant, there is a marked diurnal variation c) C. Urinary creatinine levels give a measure of muscle mass d) D. Excretion of creatinine is urine of adults is very constant from day-to-day e) E. Cratinine is an anhydride of creatine-(P) 25) Phenylketonuria is an inherited disorder due to deficiency of the enzyme: a) A. Transaminase b) B. Homogentisate oxidase c) C. Phenylalanine hydroxylase d) D. Isomerase e) E. None of the above 26) Which of the following amino acids on degradation produces a glucogenic intermediateof TCA cycle and ketone body? a) A. Glycin  b) B. Phenylalanine c) C. Alanine d) D. Cysteine e) E. Serine 27) Reactions of urea cycle take place in liver cells : a) A. In cytosol b) B. Only in lysosomes c) C. In mitochondrial matrix d) D. Both cytosol and mitochondrial matrix. e) E. Both cytosol and lysosomes 28) Depletion of a-ketoglutarate during increased NH3 influx leads to the formatin of : a) A. Arginine b) B. Proline c) C. Glutamine d) D. Histamine e) E. Serine 29) Which of the following amino acids produce a vasodilator on decarboxylation: a) A. Glutamic acid b) B. Histidine c) C. Ornithine d) D. Cysteine e) E. Arginine 30) Breakdown of amino acid tryptophan begins with formation of: a) A. Urocanic acid b) B. Nicotinic acid c) C. Anthranilic acid d) D. N-formyl kynurenine e) E. None of the above 31) During degradation of amino acid leucine to acetyl-CoA, it produces which compoundthat help in cholesterol biosynthesis: a) A. -CoA b) B. Isopentenyl pyrophosphate c) C. β-OH-β-methyl glutaryl-CoA d) D. Isovaleryl-CoA e) E. All of the above 32) Urinary oxalates in small quantities may arise from: a) A. Tyrosine  b) B. Glycine c) C. Serine d) D. Citrates e) E. Oxaloacetate 33) In humans the sulphur of methionine and cysteine is excreted mainly as: a) A. Ethereal SO4 b) B. Inorganic SO4 c) C. Sulphites d) D. Taurocholates e) E. Cysteic acid 34) A high ATP/AMP ratio will inhibit which of the following enzyme? a) A. Glyceraldehyde-3-P dehydrogenase b) B. Pyruvate kinase c) C. Enolase d) D. Phosphofructokinase e) E. Glucose-6-P dehydrogenase 35) Increased citric acid levels in the blood will stimulate which of the enzyme? a) A. Transketolase b) B. Pyruvate carboxylase c) C. Acetyl-CoA carboxylase d) D. Transaldolase e) E. Enolase 36) hypochromic microcytic anaemia with increased Fe stores in the bone marrow may be: a) A. Folic acid responsive b) B. Vitamin B12 responsive c) C. Pyridoxine responsive d) D. Vitamin C responsive e) E. Iron responsive 37) A deficiency of copper affects the formation of normal collagen by reducing the activityof which of the following enzyme? a) A. Prolyl hydroxylase  b) B. Lysyl oxidase c) C. Lysyl hydroxylase d) D. transferase e) E. Galactosyl transferase 38) Molecular iron (Fe), is: a) A. Stored primarily in spleen b) B. Absorbed in the intestine by transferrin c) C. Absorbed in the ferric, Fe+++ form d) D. Stored in the body in combination with ferritin e) E. Excreted in the urine as Fe++ 39) All the following statements regarding calcium are correct except: a) A. It diffuses as a divalent cation b) B. It freely diffuses across the endoplamic reticulum of muscle cells c) C. It can exist in the blood as ionic form and also protein bound d) D. It is found in high concentration in bones e) E. Required as a cofactor in some of reactions 40) Iron is absorbed from: a) A. Stomach  b) B. Duodenum and jejunum c) C. IIeum d) D. Caecum e) E. Transverse colon 41) The normal route of calcium excretion is: a) A. Kidney b) B. Kidney and liver c) C. Kidney and intestine d) D. Kidney, intestine and pancreas e) E. Pancreas, liver and kidney 42) Hypocalcaemia affects: a) A. Skeletal muscles b) B. Smooth muscles c) C. Cardiac muscles d) D. Skeletal muscles + smooth muscles e) E. Skeletal muscles + smooth muscles + cardiac muscles 43) Transferrin is a type of: a) A. Albumin  b) B. -globulin c) C. 1-globulin d) D. -globulin e) E. A lipoprotein complex 44) In case of Wilson‟s disease (hepatolenticular degeneration), the features include all of thefollowing, except: a) A. Progressive hepatic cirrhosis b) B. Kayser-Fleischer ring c) C. Aminoaciduria d) D. Urinary excretion of Cu is decreased e) E. Low levels of caeruloplasmin 45) In vitamin D poisoning (hypervitaminosis): a) A. Both serum and urinary Ca are high b) B. The serum Ca is low and urinary calcium high c) C. The serum Ca is increased and urinary Ca is normal d) D. Both serum and urinary Ca are low e) E. None of the above 46) The % of K in extracellular fluid is about: a) A. 1%  b) B. 2 to 3% c) C. 10% d) D. 15% e) E. 20% 47) The Fe containing pigments are: a) A. Haematoidin  b) B. Bilirubin c) C. Haemosiderin d) D. Urobilinogen e) E. None of the above 48) All of the following are true of Wilson‟s disease, except: a) A. Low total plasma Cu  b) B. Elevated urinary copper c) C. Arthritis d) D. Aminoaciduria e) E. Low caeruloplasmin 49) An increased serum iron and decreased Fe-binding capacity are found in: a) A. Fe-deficiency anaemia b) B. Sideroblastic anaemia c) C. Thalassaemia d) D. Anaemia of chronic disorders e) E. All of the above 50) Iron therapy is ineffective in which of the following conditions: a) A. Chronic blood loss b) B. Inadequate Fe-intake in diet c) C. Hypochromic anaemia of pregnancy d) D.Thalassaemia minor(-chain thalassaemia) e) E. Impaired absorption of Fe 51) In haemochromatosis, the liver is infiltrated with: a) A. Copper  b) B. Iron c) C. Manganese d) D. Chromium e) E. Lipids 52) All of the following are true of hypochromic anaemias not due to iron deficiency, except: a) A. Serum Fe is high b) B. Normal or low transferrin c) C. Stainable iron in bone marrow d) D. Vitamin B6 deficiency e) E. Iron therapy is effective 53) Cytosolic superoxide dismutase contains: a) A. Zn only  b) B. Copper only c) C. Zn and Cu both d) D. Manganese e) E. Cu and Mn both 54) A rise in blood Ca may indicate: a) A. Paget‟s disease  b) B. Vitamin D deficiency c) C. Cushing disease d) D. Hypervitaminosis D e) E. All of the above 55) The essential trace element which catalyses the formation of Hb in the body is: a) A. Mn  b) B. Se c) C. Mg d) D. Cu e) E. Fe 56) Zinc is a constituent of the enzyme: a) A. Succinate dehydrogenase b) B. Carbonic anhydrase c) C. Mitochondrial superoxide dismutase d) D. Aldolase e) E. Amylase 57) The active transport of Ca is regulated by ________, which is synthesised in kidneys: a) A. Cholecalciferol b) B. Ergosterol c) C. 25-OH cholecalciferol d) D. 1,25-diOH-cholecalciferol e) E. All of the above 58) Caeruloplasmin shows the activity of: a) A. As ferroxidase  b) B. As reductase c) C. As ligase d) D. As transferase e) E. As hydrolase 59) Which coenzyme is not involved in oxidative decarboxylation of pyruvic acid? a) A. TPP  b) B. Lipoic acid c) C. Mg++ d) D. Biotin e) E. CoA-SH 60) FAD is a coenzyme in a reaction catalysed by which of the following enzymes? a) A. β-ketothiolase b) B. Acyl-CoA synthetase c) C. Acy-CoA dehydrogenase d) D. Hydroxy acyl-CoA dehydrogenase \ e) E.  2-enoyl-CoA dehydrogenase 61) Retinal is reduced to retional by the enzyme retinene reductase in presence of whichcoenzyme: a) A. NADP+  b) B. NADPH + H+ c) C. NAD+ d) D. NADH + H+ e) E. FAD+ 62) Retinol is transported in the blood as attached to: a) A. Albumin  b) B. α1-Globulin c) C. α2-globulin d) D. β-globulin e) E. α-gobulin 63) Vitamin K2 was originally isolated from: a) A. Soyabean b) B. Putrid fish meal c) C. Alfalfa d) D. Oysters e) E. Wheat germs 64) The following forms of vitamin A is used in the visual cycle of Wald a) A. Retinol  b) B. Retinoic acid c) C. Retinaldehyde d) D. Retinyl palmitate e) E. Retinyl acetate 65) Increased carbohydrate consumption increases the dietary requirement for: a) A. Thiamine  b) B. Riboflavine c) C. Pyridoxine d) D. Folic acid e) E. Niacin 66) Pyridoxal-P is a cofactor for which of the following enzymatic reactions: a) A. Fixation of CO2 b) B. Decarboxylation reaction c) C. Phosphate group transfer d) D. Transmethylation reaction e) E. Dehydrogenase reaction 67) The disease pellagra is due to a deficiency of a) A. Vitamin B6 b) B. Nicotinic acid c) C. Pantothenic acid d) D. Folic acid e) E. Biotin 68) Increased protein intake is accompanied by an increaseddietary requirement for: a) A. Ascorbic acid  b) B. Thiamine c) C. Riboflavine d) D. Folic acid e) E. Nicotinic acid 69) The “xanthurenic index” can be used to measure pyridoxine deficiency, it involves themetabolism of: a) A. Tryptophan  b) B. Tyrosine c) C. Histidine d) D. Glycine e) E. Methionine 70) The absorption of light by cells in the retina of the eyeresults in the conversion of: a) A. All trans-retinal to cis-retinal b) B. Cis-retinal to all trans-retinal c) C. Retinal to retinol d) D. Retinol to retinal e) E. β-carotene to retinal 71) The deficiency of which one of the following vitamin causes creatinuria: a) A. Vitamin E  b) B. Vitamin K c) C. Vitamin A d) D. Vitamin B6 e) E. Vitamin B1 72) Which of the following coenzyme is involved in the formation of hydorxy-proline duringcollagen synthesis? a) A. Pyridoxal-P  b) B. TPP c) C. Cobamide coenzyme d) D. Biotin e) E. Ascorbic acid 73) biochemical indication of vitamine B12 deficiency can be obtained by measuring theurinary excretion of: a) A. Pyruvic acid  b) B. Lactic acid c) C. Malic acid d) D. Methyl malonic acid e) E. Urocanic acid 74) Which of the following characteristic would be seen in a patient with severe deficiency ofthiamine? a) A. A decreased level of pyruvic acid b) B. A decreased level of lactic acid c) C. A decreased red cells transminase activity d) D. A decreased red cells transaldolase activity e) E. A decreased red cells transketolase activity 75) To prevent rickets in case of chronic renal disorders, which of the following substancesshould be administered? a) A. Cholecalciferol b) B. Ergocalciferol c) C. 25-OH-calciferol d) D. 1,25-di-OH-cholecalciferol e) E. High dietary calcium 76) „Chastek paralysis” described in foxes is due to eating of a) A. Raw polar Bear‟s liver  b) B. Raw fish c) C. Cereals d) D. Leguminous plants e) E. None of the above 77) Which of the following vitamins is associated with synthesis of coagulation factorprothrombin? a) A. Vitamin A  b) B. Vitamin C c) C. Vitamin K d) D. Vitamin E e) E. Vitamin D 78) The visual impulse is associated with the: a) A. Transport of cis-retinal from liver to retina, b) B. Dissociation of rhodopsin into trans-retinal and opsin c) C. Dissociation of rhodopsin into cis-retianl and opsin d) D. Condensation of opsin with trans-retinal e) E. Reduction of NADP+ 79) „Bracken‟ disease describe in grazing animals is due to feeding of: a) A. Cereals b) B. Grass c) C. Leguminous plants d) D. Ferns e) E. Soyabeans 80) Sulphadrugs interfere with bacterial synthesis of: a) A. Vitamin E  b) B. Coenzyme A c) C. Lipoate d) D. Vitamin D e) E. Tetrahydrofolate (F.H4) 81) In biotin-containing enzymes, the biotin is tightly bound to the enzyme via: a) A. An amide linkage to the -amino group of the protein b) B. An amide linkage to the-amino group of lysine c) C. An amide linkage to the-carboxyl group of the protein d) D. -An amide linkage to the-carboxyl group of glutamate e) E. A covalent bond with CO2 82) Which of the following statements regarding vitamins is correct? a) A. All coenzymes contain vitamins or are vitamins. b) B. All vitamins can act as coenzymes. c) C. Prostaglandins can be derived from fat soluble vitamins d) D. All water-soluble vitamins act as coenzymes or coenzyme precursors. e) E. Ergosterol is provitamin A 83) Which of the following vitamins would most likely become deficient whose staple diet ismaize? a) A. Ribolfavin  b) B. Thiamine c) C. Niacin d) D. Pantothenic acid e) E. Ascorbic acid 84) Pantothenic acid is a constituent of the coenzyme involved in: a) A. Dehydrogenation  b) B. Acetylation c) C. Decarboxylation d) D. Reduction e) E. Oxidation 85) Biotin is involved in which of the following types of reactions? a) A. Deaminations  b) B. Hydroxylation c) C. Oxidation d) D. Reduction e) E. Carboxylation

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