ENZYMES MCQs

1. The compound which has the lowest density is
(A) Chylomicron (B) -Lipoprotein
(C) -Lipoprotein (D) pre -Lipoprotein
2. Non steroidal anti inflammatory drugs, such as aspirin act by inhibiting the activity of the enzyme:
(A) Lipoxygenase (B) Cyclooxygenase
(C) Phospholipase A2 (D) Lipoprotein lipase
3. From arachidonate, synthesis of prostag- landins is catalysed by
(A) Cyclooxygenase
(B) Lipoxygenase
(C) Thromboxane synthase
(D) Isomerase
4. A Holoenzyme is
(A) Functional unit (B) Apo enzyme
(C) Coenzyme (D) All of these
5. Gaucher’s disease is due to the deficiency of the enzyme:
(A) -Fucosidase (B) -Galactosidase
(C) -Glucosidase (D) Sphingomyelinase
6. Neimann-Pick disease is due to the defi- ciency of the enzyme:
(A) Hexosaminidase A and B
(B) Ceramidase
(C) Ceramide lactosidase
(D) Sphingomyelinase

7. Krabbe’s disease is due to the deficiency of the enzyme:
(A) Ceramide lactosidase
(B) Ceramidase
(C) -Galactosidase
(D) GM1 -Galactosidase
8. Fabry’s disease is due to the deficiency of the enzyme:
(A) Ceramide trihexosidase
(B) Galactocerebrosidase
(C) Phytanic acid oxidase
(D) Sphingomyelinase
9. Farber’s disease is due to the deficiency of the enzyme:
(A) -Galactosidase
(B) Ceramidase
(C) -Glucocerebrosidase
(D) Arylsulphatase A.
10. A synthetic nucleotide analogue, used in organ transplantation as a suppressor of immunologic rejection of grafts is
(A) Theophylline
(B) Cytarabine
(C) 4-Hydroxypyrazolopyrimidine
(D) 6-Mercaptopurine

11. Example of an extracellular enzyme is
(A) Lactate dehydrogenase
(B) Cytochrome oxidase
(C) Pancreatic lipase
(D) Hexokinase
12. Enzymes, which are produced in inactive form in the living cells, are called
(A) Papain (B) Lysozymes
(C) Apoenzymes (D) Proenzymes
13. An example of ligases is
(A) Succinate thiokinase
(B) Alanine racemase
(C) Fumarase
(D) Aldolase
14 An example of lyases is
(A) Glutamine synthetase
(B) Fumarase
(C) Cholinesterase
(D) Amylase
15. Activation or inactivation of certain key regulatory enzymes is accomplished by covalent modification of the amino acid:
(A) Tyrosine (B) Phenylalanine
(C) Lysine (D) Serine
16. The enzyme which can add water to a carbon-carbon double bond or remove water to create a double bond without breaking the bond is
(A) Hydratase (B) Hydroxylase
(C) Hydrolase (D) Esterase
17. Fischer’s ‘lock and key’ model of the enzyme action implies that
(A) The active site is complementary in shape to that of substance only after interaction.
(B) The active site is complementary in shape to that of substance
(C) Substrates change conformation prior to active site interaction
(D) The active site is flexible and adjusts to substrate

18. From the Lineweaver-Burk plot of Michaelis-Menten equation, Km and Vmax can be determined when V is the reaction velocity at substrate concentra- tion S, the X-axis experimental data are expressed as
(A) 1/V (B) V
(C) 1/S (D) S
19. A sigmoidal plot of substrate concentra- tion ([S]) verses reaction velocity (V) may indicate
(A) Michaelis-Menten kinetics
(B) Co-operative binding
(C) Competitive inhibition
(D) Non-competitive inhibition
20. The Km of the enzyme giving the kinetic data as below is
(A) –0.50 (B) –0.25
(C) +0.25 (D) +0.33
21. The kinetic effect of purely competitive inhibitor of an enzyme
(A) Increases Km without affecting Vmax
(B) Decreases Km without affecting Vmax
(C) Increases Vmax without affecting Km
(D) Decreases Vmax without affecting Km
22. If curve X in the graph (below) represents no inhibition for the reaction of the enzyme with its substrates, the curve representing the competitive inhibition, of the same reaction is
(A) A (B) B
(C) C (D) D
23. An inducer is absent in the type of enzyme:
(A) Allosteric enzyme
(B) Constitutive enzyme
(C) Co-operative enzyme
(D) Isoenzymic enzyme
24. A demonstrable inducer is absent in
(A) Allosteric enzyme (B) Constitutive enzyme
(C) Inhibited enzyme (D) Co-operative enzyme

25. In reversible non-competitive enzyme activity inhibition
(A) Vmax is increased
(B) Km is increased
(C) Km is decreased
(D) Concentration of active enzyme is reduced
26. In reversible non-competitive enzyme activity inhibition
(A) Inhibitor bears structural resemblance to substrate
(B) Inhibitor lowers the maximum velocity attainable with a given amount of enzyme
(C) Km is increased
(D) Km is decreased
27. In competitive enzyme activity inhibition
(A) The structure of inhibitor generally resembles that of the substrate
(B) Inhibitor decreases apparent Km
(C) Km remains unaffective
(E) Inhibitor decreases Vmax without affecting Km
28. In enzyme kinetics Vmax reflects
(A) The amount of an active enzyme
(B) Substrate concentration
(C) Half the substrate concentration
(D) Enzyme substrate complex
29. In enzyme kinetics Km implies
(A) The substrate concentration that gives one half Vmax
(B) The dissocation constant for the enzyme substrate comples
(C) Concentration of enzyme
(D) Half of the substrate concentration required to achieve Vmax
30. In competitive enzyme activity inhibition
(A) Apparent Km is decreased
(B) Apparent Km is increased

32. An enzyme catalyzing oxidoreduction, using oxygen as hydrogen acceptor is
(A) Cytochrome oxidase
(B) Lactate dehydrogenase
(C) Malate dehydrogenase
(D) Succinate dehydrogenase
33. The enzyme using some other substance, not oxygen as hydrogen acceptor is
(A) Tyrosinase
(B) Succinate dehydrogenase
(C) Uricase
(D) Cytochrome oxidase
34. An enzyme which uses hydrogen acceptor as substrate is
(A) Xanthine oxidase
(B) Aldehyde oxidase
(C) Catalase
(D) Tryptophan oxygenase
35. Enzyme involved in joining together two substrates is
(A) Glutamine synthetase
(B) Aldolase
(C) Gunaine deaminase
(D) Arginase
36. The pH optima of most of the enzymes is
(A) Between 2 and 4 (B) Between 5 and 9
(C) Between 8 and 12(D) Above 12
37. Coenzymes are
(A) Heat stable, dialyzable, non protein organic molecules
(B) Soluble, colloidal, protein molecules
(C) Structural analogue of enzymes
(D) Different forms of enzymes
38. An example of hydrogen transferring coenzyme is

(C) V

max

is increased

(A) CoA (B) NAD+

(D) Vmax is decreased
31. In non competitive enzyme activity inhi- bition, inhibitor
(A) Increases Km (B) Decreases Km
(C) Does not effect Km (D) Increases Km

(C) Biotin (D) TPP
39. An example of group transferring coenzyme is
(A) NAD+ (B) NADP+
(C) FAD (D) CoA

40. Cocarboxylase is
(A) Thiamine pyrophosphate
(B) Pyridoxal phosphate
(C) Biotin
(D) CoA
41. A coenzyme containing non aromatic hetero ring is
(A) ATP (B) NAD
(C) FMN (D) Biotin
42. A coenzyme containing aromatic hetero ring is
(A) TPP (B) Lipoic acid
(C) Coenzyme Q (D) Biotin
43. Isoenzymes are
(A) Chemically, immunologically and electro- phoretically different forms of an enzyme
(B) Different forms of an enzyme similar in all properties
(C) Catalysing different reactions
(D) Having the same quaternary structures like the enzymes
44. Isoenzymes can be characterized by
(A) Proteins lacking enzymatic activity that are necessary for the activation of enzymes
(B) Proteolytic enzymes activated by hydrolysis
(C) Enzymes with identical primary structure
(D) Similar enzymes that catalyse different reaction
45. The isoenzymes of LDH
(A) Differ only in a single amino acid
(B) Differ in catalytic activity
(C) Exist in 5 forms depending on M and H monomer contents
(D) Occur as monomers
46. The normal value of CPK in serum varies between
(A) 4–60 IU/L (B) 60–250 IU/L
(C) 4–17 IU/L (D) > 350 IU/L
47. Factors affecting enzyme activity:
(A) Concentration (B) pH
(C) Temperature (D) All of these

48. The normal serum GOT activity ranges from
(A) 3.0–15.0 IU/L (B) 4.0–17.0 IU/L
(C) 4.0–60.0 IU/L (D) 0.9–4.0 IU/L
49. The normal GPT activity ranges from (A) 60.0–250.0 IU/L (B) 4.0–17.0 IU/L (C) 3.0–15.0 IU/L (D) 0.1–14.0 IU/L
50. The normal serum acid phosphatase activity ranges from
(A) 5.0–13.0 KA units/100 ml
(B) 1.0–5.0 KA units/100 ml (C) 13.0–18.0 KA units/100 ml
(D) 0.2–0.8 KA units/100 ml
51. The normal serum alkaline phosphatase activity ranges from
(A) 1.0–5.0 KA units/100 ml
(B) 5.0–13.0 KA units/100 ml
(C) 0.8–2.3 KA units/100 ml (D) 13.0–21.0 KA units/100 ml
52. In early stages of myocardial ischemia the most sensitive indicator is the measurement of the activity of
(A) CPK (B) SGPT
(C) SGOT (D) LDH
53. Serum acid phosphatase level increases in
(A) Metastatic carcinoma of prostate
(B) Myocardial infarction
(C) Wilson’s disease
(D) Liver diseases
54. Serum alkaline phosphatase level increases in
(A) Hypothyroidism
(B) Carcinoma of prostate
(C) Hyperparathyroidism
(D) Myocardial ischemia
55. Serum lipase level increases in
(A) Paget’s disease (B) Gaucher’s disease
(C) Acute pancreatitis (D) Diabetes mellitus
56. Serum ferroxidase level decreases in
(A) Gaucher’s disease (B) Cirrhosis of liver
(C) Acute pancreatitis (D) Wilson’s disease

57. The isoenzymes LDH5 is elevated in
(A) Myocardial infarction
(B) Peptic ulcer
(C) Liver disease
(D) Infectious diseases
58. On the third day of onset of acute myo- cardial infarction the enzyme elevated is
(A) Serum AST (B) Serum CK
(C) Serum LDH (D) Serum ALT
59. LDH1 and LDH2 are elevated in
(A) Myocardial infarction
(B) Liver disease
(C) Kidney disease
(D) Brain disease
60. The CK isoenzymes present in cardiac muscle is
(A) BB and MB (B) MM and MB
(C) BB only (D) MB only
61. In acute pancreatitis, the enzyme raised in first five days is
(A) Serum amylase
(B) Serum lactic dehydrogenase
(C) Urinary lipase
(D) Urinary amylase
62. Acute pancreatitis is characterised by
(A) Lack of synthesis of zymogen enzymes
(B) Continuous release of zymogen enzymes into the gut
(C) Premature activation of zymogen enzymes
(D) Inactivation of zymogen enzymes
63. An example of functional plasma enzyme is
(A) Lipoprotein lipase
(B) Amylase
(C) Aminotransferase
(D) Lactate dehydrogenase
64. A non-functional plasma enzyme is
(A) Psudocholinesterase
(B) Lipoprotein lipase
(C) Proenzyme of blood coagulation
(D) Lipase

65. The pH optima for salivary analyse is
(A) 6.6–6.8 (B) 2.0–7.5
(C) 7.9 (D) 8.6
66. The pH optima for pancreatic analyse is
(A) 4.0 (B) 7.1
(C) 7.9 (D) 8.6
67. The pH optima for sucrase is
(A) 5.0–7.0 (B) 5.8–6.2
(C) 5.4–6.0 (D) 8.6
68. The pH optima for maltase is
(A) 1.0–2.0 (B) 5.2–6.0
(C) 5.8–6.2 (D) 5.4–6.0
69. The pH optima for lactase is
(A) 1.0-2.0 (B) 5.4–6.0
(C) 5.0–7.0 (D) 5.8–6.2
70. The substrate for amylase is
(A) Cane sugar (B) Starch
(C) Lactose (D) Ribose
71. The ion which activates salivary amylase activity is
(A) Chloride (B) Bicarbonate
(C) Sodium (D) Potassium
72. The pancreatic amylase activity is in- creased in the presence of
(A) Hydrochloric acid (B) Bile salts
(C) Thiocyanate ions (D) Calcium ions
73. A carbohydrate which can not be digest- ed in human gut is
(A) Cellulose (B) Starch
(C) Glycogen (D) Maltose
74. The sugar absorbed by facilitated diffusion and requiring Na independent transporter is
(A) Glucose (B) Fructose
(C) Galactose (D) Ribose
75. In the intestine the rate of absorption is highest for
(A) Glucose and galactose
(B) Fructose and mannose
(C) Fructose and pentose
(D) Mannose and pentose

76. Glucose absorption is promoted by
(A) Vitamin A (B) Thiamin
(C) Vitamin C (D) Vitamin K
77. The harmone acting directly on intestinal mucosa and stimulating glucose absorption is
(A) Insulin (B) Glucagon
(C) Thyroxine (D) Vasopressin
78. Given that the standard free energy change (G°) for the hydrolysis of ATP is
–7.3 K cal/mol and that for the hydrolysis of Glucose 6-phosphate is –3.3 Kcal/mol, the G° for the phosphorylation of glucose is Glucose + ATP  Glucose 6– Phosphate + ADP.
(A) –10.6 Kcal/mol (B) –7.3 Kcal/mol
(C) –4.0 Kcal/mol (D) +4.0 Kcal/mol
79. At low blood glucose concentration, brain but not liver will take up glucose. It is due to the
(A) Low Km of hexokinase
(B) Low Km of glucokinase
(C) Specificity of glucokinase
(D) Blood brain barrier
80. In the reaction below, Nu TP stands for NuTP + glucose  Glucose 6–Phosphate
+ NuDP.
(A) ATP (B) CTP
(C) GTP (D) UTP
81. In the figures shown below, fructose 1,6- biphosphate is located at point:
(A) A (B) B
(C) C (D) D
82. The enzyme of the glycolic pathway, sensitive to inhibiton by fluoride ions is
(A) Hexokinase (B) Aldolase
(C) Enolase (D) Pyruvate kinase
83. In glycolytic pathway, iodacetate inhibits the activity of the enzyme:
(A) Phosphotriose isomerase
(B) Glyceraldehyde-3-phosphate dehydrogenase
(C) Pyruvate kinase
(D) Phosphofructokinase

84. In the glycolytic pathway, enolpyruvate is converted to ketopyruvate by
(A) Pyruvate kinase
(B) Phosphoenolpyruvate
(C) Pyruvate dehydrogenase
(D) Spontaneously
85. In erythrocytes, 2, 3-biphosphoglycerate is derived from the intermediate:
(A) Glyeraldehyde-3-phosphate
(B) 1, 3-Biphosphoglycerate
(C) 3-Phosphoglycerate
(D) 2-Phosphoglycerate
86. 2, 3-Biphosphoglycerate in high concen- trations, combines with hemoglobin, causes
(A) Displacement of the oxyhemoglobin dissociation curve to the left
(B) Displacement of the oxyhemoglobin dissociation curve to the right
(C) No change in oxy hemoglobin dissociation curve
(D) Increased affinity for oxygen
87. Erythrocytes under normal conditions and microorganisms under anaerobic condi- tions may accumulate
(A) NADPH
(B) Pyruvate
(C) Phosphoenolpyruvate
(D) Lactate
88. Enzymes leading to the high energy phosphorylation of substrates during glycolysis include which of the following?
(A) Phosphoglycerate kinase
(B) Enolase
(C) Pyruvate Kinase
(D) Glyceraldehyde-3-phosphate dehydrogenase
89. Lineweaver – Burk double reciprocal plot is related to
(A) Substrate concentration
(B) Enzyme activity
(C) Temperature
(D) Both (A) and (B)

90. Phosphofructokinase key enzyme in glycolysis is inhibited by
(A) Citrate and ATP (B) AMP
(C) ADP (D) TMP
91. One of the enzymes regulating glycolysis is
(A) Phosphofructokinase
(B) Glyceraldehyde-3-phosphate dehydrogenase
(C) Phosphotriose isomerase
(D) Phosphohexose isomerase
92. Hexokinase is inhibited in an allosteric manner by
(A) Glucose-6-Phosphate
(B) Glucose-1-Phosphate
(C) Fructose-6-phosphate
(D) Fructose-1, 6-biphosphate
93. A reaction which may be considered an isomerisation is
(A) Glucose 6-Phosphate fructose 6 phosphate
(B) 3-Phosphoglycerate 2-phosphoglycerate
(C) 2-phosphoglycerate phosphoenol- pyruvate
(D) Pyruvate Lactate
94. The net number of ATP formed per mole of glucose in anaerobic glycolysis is
(A) 1 (B) 2
(C) 6 (D) 8
95. Pyruvate dehydrogenase a multienzyme complex is required for the production of
(A) Acetyl-CoA
(B) Lactate
(C) Phosphoenolpyruvate
(D) Enolpyruvate
96. Dietary deficiency of thiamin inhibits the activity of the enzyme:
(A) Pyruvate kinase
(B) Pyruvate dehydrogenase
(C) Phosphofructokinase
(D) Enolase

97. Pyruvate dehydrogenase activity is inhibited by
(A) Mercury (B) Zinc
(C) Calcium (D) Sodium
98. In the normal resting state of humans, most of the blood glucose burned as fuel is consumed by
(A) Liver (B) Adipose tissue
(C) Muscle (D) Brain
99. All the enzymes of glycolysis pathway are found in
(A) Extramitochondrial soluble fraction of the cell
(B) Mitochondria
(C) Nucleus
(D) Endoplasmic reticulum
100. Most major metabolic pathways are con- sidered mainly either anabolic or cata- bolic. Which of the following pathway is most correctly considered to be am- phibolic?
(A) Citric acid cycle (B) Gluconeogenesis
(C) Lipolysis (D) Glycolysis
101. The enzymes of the citric acid cycle are located in
(A) Mitochondrial matrix
(B) Extramitochondrial soluble fraction of the cell
(C) Nucleus
(D) Endoplasmic reticulum
102. The initial step of the citric acid cycle is
(A) Conversion of pyruvate to acetyl-CoA
(B) Condensation of acetyl-CoA with oxaloacetate
(C) Conversion of citrate to isocitrate
(D) Formation of  -ketoglutarate catalysed by isocitrate dehydrogenase
103. The substance which may be considered to play a catalytic role in citric acid cycle is
(A) Oxaloacetate (B) Isocitrate
(C) Malate (D) Fumarate
104. An enzyme of the citric acid cycle also found outside the mitochondria is
(A) Isocitrate dehydrogenase
(B) Citrate synthetase
(C) -Ketoglutarate dehydrogenase
(D) Malate dehydrogenase

105. The reaction catalysed by -ketoglutarate dehydrogenase in the citric acid cycle requires
(A) NAD (B) NADP
(C) ADP (D) ATP
106. If all the enzymes, intermediates and cofactors of the citric acid cycle as well as an excess of the starting substrate acetyl- CoA are present and functional in an organelle free solution at the appropriate pH, which of the following factors of the citric acid cycle would prove to be rate limiting ?
(A) Molecular oxygen
(B) Half life of enzyme
(C) Turnover of intermediates
(D) Reduction of cofactors
107. In TCA cycle, oxalosuccinate is converted to -ketoglutarate by the enzyme:
(A) Fumarase
(B) Isocitrate dehydrogenase
(C) Aconitase
(D) Succinase
108. The enzyme -ketoglutarate dehydrogena- se in the citric acid cycle requires
(A) Lipoate (B) Folate
(C) Pyridoxine (D) Inositol
109. The example of generation of a high energy phosphate at the substrate level in the citric acid cycle is the reaction:
(A) Isocitrate -Ketoglutarate
(B) Succinate -fumarate
(C) Malate -oxaloacetate
(D) Succinyl CoA -Succinate
110. Fluoroacetate inhibits the reaction of citric acid cycle:
(A) Isocitrate -Ketoglutarate
(B) Fumarate -Malate
(C) Citrate -cis-aconitate
(D) Succinate -fumarate

111. Formation of succinyl-CoA from -Keto- glutarate is inhibited by
(A) Fluoroacetate (B) Arsenite
(C) Fluoride (D) Iodoacetate
112. The number of ATP molecules generated for each turn of the citric acid cycle is
(A) 8 (B) 12
(C) 24 (D) 38
113. Oxidation of one molecule of glucose yields
(A) 12 ATP (B) 24 ATP
(C) 38 ATP (D) 38 ATP
114. Which of the following intermediates of metabolism can be both a precursor and a product of glucose?
(A) Lactate (B) Pyruvate
(C) Alanine (D) Acetyl-CoA
115. Mitochondrial membrane is freely preamble to
(A) Pyruvate (B) Malate
(C) Oxaloacetate (D) Fumarate
116. The reaction of Kreb’s cycle which does not require cofactor of vitamin B group is
(A) Citrate isocitrate
(B)  -Ketoglutarate succinate
(C) Malate oxaloacetate
(D) Succinate fumarate
117. The coenzyme not involved in the formation of acetyl-CoA from pyruvate is
(A) TPP (B) Biotin
(C) NAD (D) FAD
118. A carrier molecule in the citric acid cycle is
(A) Acetyl-CoA (B) Citrate
(C) Oxaloacetate (D) Malate
119. A specific inhibitor for succinate dehydro- genase is
(A) Arsenine (B) Arsenite
(C) Citrate (D) Fluoride

120. The rate of citric acid cycle is controlled by the allosteric enzyme:
(A) Aconitase
(B) Fumarase
(C) Fumarase
(D) Malate dehydrogenase
121. In the erythrocytes, the net production of ATP molecules by the Rapport-Leubering pathway is
(A) 0 (B) 2
(C) 4 (D) 8
122. The ratio that most closely approximates the number of net molecules of ATP formed per mole of glucose utilized under aerobic conditions to the net number formed under anaerobic conditions is
(A) 4:1 (B) 13:1
(C) 18:1 (D) 24:1
123. The pathway of glycogen biosynthesis involves a special nucleotide of glucose. In the reaction below, NuDP stands for
NuDP Glucose + glycogenn  NuDP + glycogenn+1
(A) ADP (B) GDP
(C) UDP (D) CDP
124. Glucose 6-phosphate is converted to glu- cose 1-phosphate in a reaction catalysed by the enzyme phosphoglucomutase, which is
(A) Phosphorylated
(B) Dephosphorylated
(C) Phosphorylated-dephosphorylated
(D) Phosphorylated-dephosphorylatedrephos- phorylated
125. The glycogen content of the liver is upto
(A) 6% (B) 8%
(C) 10% (D) 12%
126. In glycogenesis a branch point in the molecule is established by the enzyme
(A) Amylo[1 4][1 6] transglucosidase
(B)  [1 4]  [1 4] Glucan transferase
(C) Amylo [1 6] glucosidase
(D) Glycogen synthase

127. In glycogenolysis, the enzyme which transfers a trisaccharide unit from one branch to the other exposing 1 6 branch point is
(A) Phosphorylase
(B) -[1 4] -[1 4] Glucan transferase
(C) Amylo [1 6] glucosidase
(D) Amylo[1 4] [1 6] transglucosidase
128. In the synthesis of glycogen from glucose the reversible step is
(A) Glucose  glucose 6-phosphate
(B) Glucose 6-phosphate  glucose 1-phosphate
(C) Glucose 1-phosphate  UDP glucose
(D) UDP glucose  glycogen
129. The enzyme glucose-6-phosphatase which catalyses the conversion of glucose 6-phosphate to glucose is not found in
(A) Liver (B) Muscle
(C) Intestine (D) Kidney
130. Allosteric activator of glycogen synthase is
(A) Glucose (B) Glucose-6-Phosphate
(C) UTP (D) Glucose-1-phosphate
131. Action of glycogen synthase is inhibited by
(A) Insulin (B) Glucose
(C) Mg2+ (D) Cyclic AMP
132. The hormone activating the glycogen synthase activity is
(A) Insulin (B) Glucagon
(C) Epinephrine (D) ACTH
133. Characteristic features of active site are
(A) Flexible in nature (B) Site of binding
(C) Acidic (D) Both (A) and (B)
134. Von Gierke’s disease is characterized by the deficiency of
(A) Glucose-6-phosphatase
(B)  -1  4 Glucosidase
(C) 1  6 Glucosidase
(D) Liver phosphorylase

135. Cori disease (Limit dextrinosis) is caused due to absence of
(A) Branching enzyme
(B) Debranching enzyme
(C) Glycogen synthase
(D) Phosphorylase
136. Mc Ardle’s syndrome is characterized by the absence of
(A) Liver phosphorylase
(B) Muscle phosphorylase
(C) Branching enzyme
(D) Debranching enzyme
137. Pompe’s disease is caused due to deficiency of
(A) Lysosomal -14 and 16-glucosidase
(B) Glucose-6-phosphatase
(C) Glycogen synthase
(D) Phosphofructokinase
138. Amylopectinosis is caused due to absence of
(A) Debranching enzyme
(B) Branching enzyme
(C) Acid maltase
(D) Glucose-6-phosphatase
139. Her’s disease is characterized by deficien- cy of
(A) Muscle phosphorylase
(B) Liver phosphorylase
(C) Debranching enzyme
(D) Glycogen synthase
140. Tarui disease is characterized by the deficiency of the enzyme:
(A) Liver phosphorylase
(B) Muscle phosphorylase
(C) Muscle and erythrocyte phosphofructokinase
(D) Lysosomal acid maltase
141. The hexose monophosphate pathway includes the enzyme:
(A) Maltase dehydrogenase
(B) Hexokinase
(C) -Ketoglutarate dehydrogenase
(D) Glucose-6-phosphate dehydrogenase

142. The hydrogen acceptor used in pentose phosphate pathway is
(A) NAD (B) NADP
(C) FAD (D) FMN
143. The enzymes of the pentose phosphate pathway are found in the
(A) Cytosol
(B) Mitochondria
(C) Nucleus
(D) Endoplasmic reticulum
144. In pentose phosphate pathway, D-ribulose- 5-phosphate is converted to D-ribose-5- phosphate by the enzyme:
(A) Fumarase (B) Ketoisomerase
(C) G-6-PD (D) Epimerase
145. The transketolase enzyme in the pentose phosphate pathway requires the B vitamin.
(A) Pantothenic acid (B) Thiamin
(C) Riboflavin (D) Nicotinic acid
146. Xylulose-5-phosphate serves as a donar of active glycolaldehyde, the acceptor is
(A) Erythrose 4-phosphate
(B) Ribose 5-phosphate
(C) Glyceraldehyde 3-phosphate
(D) Sedoheptulose 7-phosphate
147. Pentose phosphate pathway is of signif- icance because it generates
(A) NADPH for reductive synthesis
(B) Regenerates glucose 6-phosphate
(C) Generates fructose 6-phosphate
(D) Forms glyceraldehyde 3-phosphate
148. The pentose phosphate pathway protects erythrocytes against hemolysis by assis- ting the enzyme:
(A) Superoxide dismutase
(B) Catalase
(C) Glutathionic peroxidase
(D) Cytochrome oxidase

149. Hemolytic anemia is caused by the deficiency of certain enzymes of the pentose phosphate pathway, the principal enzyme involved is
(A) Glucose-6-phosphate dehydrogenase
(B) Aldolase
(C) Fructose 1, 6-bisphosphatase
(D) Phosphohexose isomerase
150. The sites for gluconeogenesis are
(A) Liver and kidney
(B) Skin and pancreas
(C) Lung and brain
(D) Intestine and lens of eye
151. An enzyme involved in gluconeogenesis is
(A) Pyruvate kinase
(B) Pyruvate carboxylase
(C) Hexokinase
(D) Phosphohexose isomerase
152. The enzyme pyruvate carboxylase is present in
(A) Cytosol (B) Mitochondria
(C) Nucleus (D) Golgi bodies
153. The enzyme phosphoenolpyruvate carboxykinase catalyses the conversion of oxaloacetate to phosphoenolpyruvate requires
(A) ATP (B) ADP
(C) AMP (D) GTP
154. The enzyme glucose 6-phosphatase is present in
(A) Liver (B) Muscle
(C) Adipose tissue (D) Brain
155. In gluconeogensis, an allosteric activator required in the synthesis of oxaloacetate from bicarbonate and pyruvate, which is catalysed by the enzyme pyruvate carboxylase is
(A) Acetyl CoA (B) Succinate
(C) Isocitrate (D) Citrate
156. The number of ATP molecules required to convert 2 molecules of lactate into glucose in mammalian liver is
(A) 2 (B) 4
(C) 5 (D) 6

157. For conjugation with many enogenous and exogenous substances before eli- mination in urine, the uronic acid path- way provides
(A) Active glucuronate (B) Gulonate
(C) Xylulose (D) Xylitol
158. UDP glucose is converted to UDP glucurronate, a reaction catalysed by UDP glucose dehydrogenase requires
(A) NAD+ (B) FAD
(C) NADP (D) FMN
159. Pentosuria is a rare hereditary disease is characterized by increased urinary excretion of
(A) L-xylulose
(B) Xylitol
(C) Xylulose 5-phosphate
(D) Ribose 5-phosphate
160. The enzyme involved in essential pentosuria is
(A) Reductase (B) Hydroxylase
(C) Isomerase (D) Racemase
161. Galactose is synthesized from glucose in
(A) Mammary gland (B) Intestine
(C) Kidney (D) Adipose tissue
162. Galactose is readily converted to glucose in
(A) Liver (B) Intestine
(C) Kidney (D) Adipose tissue
163. Galactose 1-phosphate is converted to uridine diphosphate galactose, the reaction is catalysed by the enzyme:
(A) Glactokinase
(B) Galactose 1-phosphate uridyl transferase
(C) Uridine diphospho galactose 4-epimerase
(D) UDP glucose pyrophosphorylase
164. The best known cause of galactosemia is the deficiency of
(A) Galactose 1-phosphate and uridyl transferase
(B) Phosphoglucomutase
(C) Galactokinase
(D) Lactose synthase

165 Conversion of fructose to sorbitol is catalysed by the enzyme:
(A) Sorbitol dehydrogenase
(B) Aldose reductase
(C) Fructokinase
(D) Hexokinase
166. A specific fructokinase present in liver has a very high affinity for its substrate because
(A) Km for fructose is very high
(B) Km for fructose is very low
(C) Activity is affected by fasting
(D) Activity is affected by insulin
167. Insulin has no effect on the activity of the enzyme:
(A) Glycogen synthetase
(B) Fructokinase
(C) Pyruvate kinase
(D) Pyruvate dehydrogenase
168. The pathogenesis of diabetic cataract involves accumulation of
(A) Galactose (B) Mannitol
(C) Sorbitol (D) Pyruvate
169. Hereditary fructose intolerance involves the absence of the enzyme:
(A) Aldalose B
(B) Fructokinase
(C) Triokinase
(D) Phosphotriose isomerase
170. Essential fructosuria is characterized by the lack of the hepatic enzyme:
(A) Phosphohexose isomerase
(B) Aldalose A
(C) Aldolase B
(D) Fructokinase
171. In normal individuals glycosuria occurs when the venous blood glucose concen- tration exceeds
(A) 5–6 mmol/L
(B) 7–8 mmol/L
(C) 8.5–9 mmol/L
(D) 9.5–10 mmol/L

172. Phlorizin inhibits
(A) Renal tubular reabsorption of glucose
(B) Glycolysis
(C) Gluconeogenesis
(D) Glycogenolysis
173. Renal glycosuria is characterized by
(A) Hyperglycemia
(B) Hyperglycemia with glycosuria
(C) Normal blood glucose level with glycosuria
(D) Hyperglycemia with ketosis
174. Acute hemolytic anemia in person’s sen- sitive to the Fava beans is due to the defi- ciency of the enzyme:
(A) Pyruvate dehydrogenase
(B) G-6-PD
(C) Aconitase
(D) Transketolase
175 Acute hemolytic episode after administra- tion of antimalarial, primaquin, is due to deficiency of the enzyme:
(A) 6-Phosphogluconate dehydrogenase
(B) Glucose-6-phosphate dehydrogenase
(C) Epimerase
(D) Transketolase
176. The pH optima of gastric lipase is
(A) 3.0–6.0 (B) 1.0–2.0
(C) 8.0 (D) 8.6
177. The optimum pH of pancreatic lipase is
(A) 2.0 (B) 4.0
(C) 6.0 (D) 8.0
178. Gastric lipae is activated in the presence of
(A) Bile salts (B) Cu++
(C) K+ (D) Na+
179. An example of enzyme inhibition:
(A) Reversible inhibition
(B) Irreversible inhibition
(C) Allosteric inhibition
(D) All of these

180. The formation of 2-trans-enoyl-CoA from acyl-CoA requires the enzyme:
(A) Acyl-CoA synthetase
(B) Acyl-CoA dehydrogenase
(C) 3-Hydroxy acyl-CoA dehydrogenase
(D) Thiolase
181. In -oxidation 3-ketoacyl-CoA is splitted at the 2, 3 position by the enzyme:
(A) Hydratase (B) Dehydrogenase
(C) Reducatse (D) Thiolase
182. Fatty acids with odd number of carbon atoms yield acetyl-CoA and a molecule of
(A) Succinyl-CoA (B) Propionyl-CoA
(C) Malonyl-CoA (D) Acetoacetyl-CoA
183 For each of the first 7-acetyl-CoA molecules formed by -oxidation of palmitic acid, the yield of high energy phosphates is
(A) 12 (B) 24
(C) 30 (D) 35
184. The net gain of ATP/mol of palmitic acid on complete oxidation is
(A) 88 (B) 105
(C) 129 (D) 135
185. -oxidation is normally a very minor pathway and is brought by hydroxylase enzymes involving
(A) Cytochrome a (B) Cytochrome b
(C) Cytochrome c (D) Cytochrome p-450
186. -Oxidation i.e., the removal of one carbon at a time from the carboxyl end of the molecule has been detected in
(A) Brain tissue (B) Liver
(C) Adipose tissue (D) Intestine
187. In -oxidation, the coenzyme for acyl-CoA dehydrogenase is
(A) FMN (B) NAD
(C) NADP (D) FAD
188. The coenzyme involved in dehydrogena- tion of 3-hydroxy acyl-CoA is
(A) FAD (B) FMN
(C) NAD (D) NADP

189. The concentration of ketone bodies in the blood does not normally exceed
(A) 0.2 mmol/L (B) 0.4 mmol/L
(C) 1 mmol/L (D) 2 mmol/L
190. In humans under normal conditions loss of ketone bodies via urine is usually less than
(A) 1 mg/24 hr (B) 4 mg/24 hr
(C) 8 mg/24 hr (D) 10 mg/24 hr
191. The structure which appears to be the only organ to add significant quantities of ketone bodies to the blood is
(A) Brain (B) Erythrocytes
(C) Liver (D) Skeletal muscle
192. The starting material for ketogenesis is
(A) Acyl-CoA (B) Acetyl-CoA
(C) Acetoacetyl-CoA (D) Malonyl-CoA
193. Enzymes responsible for ketone body formation are associated mainly with the
(A) Mitochondria
(B) Endoplasmic reticulum
(C) Nucleus
(D) Golgi apparatus
194. The synthesis of 3-hydroxy-3-methyl- glutaryl-CoA can occur
(A) Only in mitochondria of all mammalian tissues
(B) Only in the cytosol of all mammalian tissue
(C) In both cytosol and mitochondria
(D) In lysosomes
195. In the pathway leading to biosynthesis of acetoacetate from acetyl-CoA in liver, the immediate precursor of aceotacetate is
(A) Acetoacetyl-CoA
(B) 3-Hydroxybutyryl-CoA
(C) 3-Hydroxy-3-methyl-glutaryl-CoA
(D) 3-Hydroxybutyrate
196. Ketone bodies serve as a fuel for
(A) Extrahepatic tissues
(B) Hepatic tissues
(C) Erythrocytes
(D) Mitochondria

197. In extra hepatic tissues, one mechanism for utilization of acetoacetate involves
(A) Malonyl-CoA (B) Succinyl-CoA
(C) Propionyl-CoA (D) Acetyl-CoA
198. Ketosis reflects
(A) Increased hepatic glucose liberation
(B) Increased fatty acid oxidation
(C) Increased carbohydrate utilisation
(D) Incresed gluconeogenesis
199. Ketosis is associated with the disease:
(A) Nephritis
(B) Diabetes mellitus
(C) Edema
(D) Coronary artery diseases
200. The main pathway for denovo synthesis of fatty acids occur in
(A) Cytosol (B) Mitochondria
(C) Microsomes (D) Nucleus
201. Chain elongation of fatty acids in mammalian liver occurs in
(A) Nucleus (B) Ribosomes
(C) Lysosomes (D) Microsomes
202. Acetyl-CoA is the principal building block of fatty acids. It is produced within the mitochondria and does not diffuse readily into cytosol. The availability of acetyl CoA involves
(A) Carnitine acyl transferase
(B) Pyruvate dehydrogenase
(C) Citrate lyase
(D) Thiolase
203. The synthesis of fatty acids is often termed reductive synthesis.
(A) NADP+ (B) NADH
(C) FADH2 (D) NADPH
204. The protein, which is in fact a multifunc- tional enzyme complex in higher organ- ism is
(A) Acetyl transacylase
(B) Malonyl transacylase
(C) 3-Hydroxy acyl-ACP dehyratase
(D) Fatty acid synthase

205. The fatty acid synthase complex catalyses
(A) 4 sequential enzymatic steps
(B) 6 sequential enzymatic steps
(C) 7 sequential enzymatic steps
(D) 8 sequential enzymatic steps
206. The main source of reducing equivalents (NADPH) for lipogenesis is
(A) Pentose phosphate pathway
(B) Citric acid cycle
(C) Glycolysis
(D) Glycogenolysis
207. In fatty acids synthase of both bacteria and mammals, ACP (acyl carrier protein) contain the vitamin:
(A) Thiamin (B) Pyridoxine
(C) Riboflavin (D) Pantothenic acid
208. Carboxylation of acetyl-CoA to malonyl- CoA requires the enzyme:
(A) Acetyl-CoA carboxylase
(B) Pyruvate carboxylase
(C) Acetyl transacylase
(D) Acyl CoA-synthetase
209. The rate limiting reaction in the lipogenic pathway is
(A) Acetyl-CoA carboxylase step
(B) Ketoacyl synthase step
(C) Ketoacyl reductase step
(D) Hydratase step
210. Conversion of fatty acyl-CoA to an acyl- CoA derivative having 2 more carbon atoms involves as acetyl donar:
(A) Acetyl-CoA (B) Succinyl-CoA
(C) Propionyl-CoA (D) Malonyl-CoA
211. A cofactor required for the conversion of acetyl-CoA to malonyl-CoA in extramito- chondrial fatty acid synthesis is
(A) Biotin (B) FMN
(C) NAD (D) NADP
212. The glycerol for fatty acid esterification in adipocytes is
(A) For the most part, derived from glucose
(B) Obtained primarily from phosphorylation of glycerol by glycerol kinase
(C) Formed from gluconeogenesis
(D) Formed from glycogenolysis

213. In the biosynthesis of triglycerides from glycerol 3-phosphate and acyl-CoA, the first intermediate formed is
(A) 2-Monoacylglycerol
(B) 1, 2-Diacylglycerol
(C) Lysophosphatidic acid
(D) Phosphatidic acid
214. The enzyme glycerol kinase is low activity in
(A) Liver (B) Kidney
(C) Intestine (D) Adipose tissue
215. The common precursor in the biosynthesis of triacylglycerol and phospholipids is
(A) 1, 2-Diacylglycerol phosphate
(B) 1-Acylglycerol 3-phosphate
(C) Glycerol 3-phosphate
(D) Dihydroxyacetone phosphate
216. Synthesis of polyunsaturated fatty acids involves the enzyme systems:
(A) Acyl transferase and hydratase
(B) Desaturase and elongase
(C) Ketoacyl-CoA reductase and hydratase
(D) Dihydroxyacetone phosphate
217. The desaturation and chain elongation system of polyunsaturated fatty acid are enhanced by
(A) Insulin (B) Glucagon
(C) Epinephrine (D) Thyroxine
218. Higher rate of lipogenesis is associated with
(A) High proportion of carbohydrate in diet
(B) Restricted caloric intake
(C) High fat diet
(D) Deficiency of insulin
219. Example of enzyme specificity:
(A) Stereo specificity (B) Reaction specificity
(C) Substrate specificity(D) All of these
220. Phospholipase C attacks the ester bond liberating 1, 2-diacylglycerol and a phosphoryl base at position
(A) 1 (B) 2
(C) Both (A) and (B) (D) 3

221. Synthesis of phosphatidylinositol by transfer of inositol to CDP diacylglycerol is catalysed by the enzyme:
(A) CTP phosphatidate cytidyl transferase
(B) Phosphatidate phosphohydrolase
(C) CDP-diacylglycerol inositol transferase
(D) Choline kinase
222. Synthesis of sphingosine requires the cofactor
(A) NAD (B) NADP
(C) NADPH+ (D) ATP
223. Ceramide is formed by the combination of sphingosine and
(A) Acetyl-CoA (B) Acyl-CoA
(C) Malonyl-CoA (D) Propionyl-CoA
224. The amino alcohol sphingosine is synthesized in
(A) Mitochondria
(B) Cytosol
(C) Nucleus
(D) Endoplasmic reticulum
225. The output of free fatty acids from adipose tissue is reduced by
(A) Insulin (B) Glucagon
(C) Growth hormone (D) Epinephrine
226. The principal action of insulin in adipose tissue is to inhibit the activity of the
(A) Hormone sensitive lipoprotein lipase
(B) Glycerol phosphate acyltransferase
(C) Acetyl-CoA carboxylase
(D) Pyruvate dehydrogenase
227. In non shivering thermogenesis
(A) Glucose is oxidized to lactate
(B) Fatty acids uncouple oxidative phosphoryla- tion
(C) Ethanol is formed
(D) ATP is burned for heat production
228. Brown adipose tissue is
(A) A prominent tissue in human
(B) Characterised by high content of mitochon- dria
(C) Associated with high activity of ATP synthase
(D) Characterised by low content of cytochromes

229. Fatty liver is caused due to accumulation of
(A) Fatty acids (B) Cholesterol
(C) Phospholipids (D) Triacylglycerol
230. A lipotropic factor is
(A) Choline (B) Palmitic acid
(C) Calcium (D) Vitamin C
231. Fatty liver is also caused by
(A) CH Cl (B) CCl

238. In the biosynthesis of cholesterol, the step which controls the rate and locus of metabolic regulation is
(A) Geranyl pyrophosphate farnesyl pyro- phosphate
(B) Squalene  lanosterol
(C) HMG CoA  mevalonate
(D) Lanosterol  1, 4-desmethyl lanosterol
239. The cyclisation of squalene in mammals results in the direct formation of the sterol.

3 4 (A) Cholesterol (B) Lanosterol

(C) Na2SO4 (D) Riboflavin
232. All the enzymes involved in the synthesis of cholesterol are found in
(A) Mitochondria
(B) Golgi apparatus
(C) Nucleus
(D) Endoplasmic reticulum and cytosol
233. The source of all the carbon atoms in cholesterol is
(A) Acetyl-CoA (B) Bicarbonate
(C) Propionyl-CoA (D) Succinyl-CoA
234. Two molecules of acetyl-CoA condense to form acetoacetyl-CoA catalysed by
(A) Thiolase (B) Kinase
(C) Reductase (D) Isomerase
235. Acetoacetyl-CoA condenses with one more molecule of acetyl-CoA to form
(A) Mevalonate
(B) Acetoacetate
(C) -Hydroxybutyrate
(D) 3-Hydroxy 3-methyl-glutaryl-CoA
236. HMG-CoA is converted to mevalonate by reduction catalysed by
(A) HMG-CoA synthetase
(B) HMG-CoA reductase
(C) Mevalonate kinase
(D) Thiolase
237. For reduction enzyme HMG-CoA reductase requires cofactor:
(A) NADPH (B) NADP
(C) NAD (D) FAD

(C) Sistosterol (D) Zymosterol
240. In the biosynthesis of cholesterol, the rate limiting enzyme is
(A) Mevalonate kinase
(B) HMG-CoA synthetase
(C) HMG-CoA reductase
(D) Cis-prenyl transferase
241. Cholesterol by a feed back mechanism inhibits the activity of
(A) HMG-CoA synthetase
(B) HMG-CoA reductase
(C) Thilase
(D) Mevalonate kinase
242. The activity of HMG-CoA reductase is inhibited by
(A) A fungal inhibitor mevastatin
(B) Probucol
(C) Nicotinic acid
(D) Clofibrate
243. Hypolipidemic drugs reduce serum cholesterol and triacylglycerol. The effect of clofibrate is attributed to
(A) Block in absorption from G.I.T.
(B) Decrease in secretion of triacylglycerol and cholesterol containing VLDL by liver
(C) Block in the reabsorption of bile acids
(D) Decreased synthesis of cholesterol
244. In biosynthesis of cholesterol triparanol inhibits the activity of the enzyme:
(A) 24 Reductase
(B) Oxidosqualene-lanosterol cyclase
(C) Isomerase
(D) Squalene epoxidase

245. HMG-CoA reductase activity is increased by administration of the hormone:
(A) Insulin (B) Glucagon
(C) Epinephrine (D) Glucocorticoids
246. The principal sterol excreted in feces is
(A) Coprostanol (B) Zymosterol
(C) Lanosterol (D) Desmosterol
247. The principal rate limiting step in the biosynthesis of bile acids is at the
(A) 7-Hydroxylase reaction
(B) 12 -Hydroxylase reaction
(C) Conjugation reaction
(D) Deconjugation reaction
248. Hypercholesterolemia is found in
(A) Xanthomatosis
(B) Thyrotoxicosis
(C) Hemolytic jaundice
(D) Malabsorption syndrom
249. Hypocholesterolemia is found in
(A) Thyrotoxicosis
(B) Diabetes mellitus
(C) Obstructive jaundice
(D) Nephrotic syndrome
250. The major source of extracellular cholesterol for human tissue is
(A) Very low density lipoprotein
(B) High density lipoprotein
(C) Low density lipoprotein
(D) Albumin
251. Correct ordering of lipoprotein molecules from lowest to the greater density is
(A) LDL, IDL, VLDL, chylomicron
(B) Chylomicron, VLDL, IDL, LDL
(C) VLDL, IDL, LDL, chylomicron
(D) LDL, VLDL, IDL, chylomicron
252. In Hurler’s syndrome, urine shows the presence of
(A) Keratan sulphate I
(B) Chondroitin sulphate
(C) Dermatan sulphate and heparan sulphate
(D) Keratan sulphate II

253. Defective enzyme in Hunter’s syndrome is
(A) -L-iduronidase (B) Iduronate sulphatase
(C) Arylsulphatase B (D) C-acetyl transferase
254. In Hunter’s syndrome
(A) There is progressive corneal opacity
(B) Keratan sulphate is excreted in the urine
(C) Enzyme defective is arylsulphatase B
(D) Hearing loss is perceptive
255. An important feature of Von-Gierke’s disease is
(A) Muscle cramps (B) Cardiac failure
(C) Hypoglycemia (D) Respiratory alkalosis
256. The affected organ in Mc Ardle’s syndrome is
(A) Liver (B) Kidney
(C) Liver and Heart (D) Skeletal muscle
257. Refsum’s disease is due to deficiency of the enzyme:
(A) Pytantate--oxidase
(B) Glucocerebrosidase
(C) Galactocerebrosidase
(D) Ceramide trihexosidase
258. An important finding in Refsum’s disease is
(A) Accumulation of ceramide trihexoside in the kidney
(B) Accumulation of phytanic acid in the blood and tissues
(C) Accumulation of gangliosides in brain and spleen
(D) Skin eruptions
259. -Galactosidase enzyme is defective in
(A) Tay-sach’s disease
(B) Refsum’s disease
(C) Sandhoff’s disease
(D) Fabry’s disease
260. The hypothesis to explain enzyme– substrate complex formation:
(A) Lock and key model
(B) Induced fit theory
(C) Proenzyme theory
(D) Both (A) and (B)

261. An important finding in Tay-sach’s disease is
(A) Renal failure
(B) Accumulation of gangliosides in brain and spleen
(C) Cardiac failure
(D) Anemia
262. The enzyme deficient in Krabbe’s disease is
(A) Hexosaminidase A (B) Arylsuphatase A
(C) -Galactosidase (D) -Fucosidase
263. The enzyme ceramidase is deficient in
(A) Farber’s disease (B) Fabry’s disease
(C) Sandhoff’s disease(D) Refsum’s disease
264. Niemann-Pick disease is due to deficiency of the enzyme
(A) Ceramidase
(B) Glucocerebrosidase
(C) Galactocerebrosidase
(D) Sphingomyelinase
265. Wolman’s disease is due to deficiency of
(A) Cholesteryl ester hydrolase
(B) Hexosaminidase A
(C) -Fucosidase
(D) Arylsulphatase A
266. The enzyme deficient in Sandhoff’s disease is
(A) -Fucosidase
(B) Hexosaminidase A and B
(C) -Galactosidase
(D) -Glucosidase
267. Jamaican vomiting sickness is due to inactivation of the enzyme
(A) Pyruvate carboxylase
(B) Acyl-Co-A synthetase
(C) Acyl-Co-A dehydrogense
(D) Thiolase
268. Zellweger’s syndrome is due to inherited absence of
(A) Peroxisomes
(B) Phospholipase A1
(C) Acyl-Co-A dehydrogenase
(D) Thiolase

269. Bassen-Kornzweig syndrome is due to
(A) Absence of Apo-C-II
(B) Defect in Apo-B synthesis
(C) Absence of Apo-E
(D) Absence of Apo-D
270. Enzyme deficient in Hyperammonemia type II is
(A) Glutamine synthetase
(B) Glutaminase
(C) Ornithine transcarbamoylase
(D) Carbamoylphosphate synthetase
271. An important finding in Hyperammone- mia type II is
(A) Increased serum gluatmine level
(B) Enlarged liver
(C) Mental retardation
(D) Increased carbamoyl phosphate synthetase level
272. Absence of the enzyme argininosuccinate synthetase causes
(A) Argininosuccinic aciduria
(B) Hyperargininemia
(C) Tricorrhexis nodosa
(D) Citrullinemia
273. Tricorrhexis nodosa is a characteristic find- ing of
(A) Argininosuccinic aciduria
(B) Citrullinemia
(C) Phenylketonuria
(D) Hyperargininemia
274. Elevated blood argininosuccinate level is found in
(A) Hyperargininemia
(B) Argininosuccinic aciduria
(C) Citrullinemia
(D) Tyrosinosis
275. Hyperargininemia, a defect in urea syn- thesis develops due to deficiency of the enzyme:
(A) Ornithine transcarbamoylase
(B) Argininosuccinase
(C) Arginase
(D) Argininosuccinate synthetase

276. Albinism is due to deficiency of the enzyme:
(A) Phenylalanine hydroxylase
(B) Tyrosinase
(C) p-Hydroxyphenylpyruvic acid oxidase
(D) Tyrosine dehydrogenase
277. Neonatal tyrosinemia is due to deficiency of the enzyme:
(A) p-Hydroxyphenylpyruvate hydroxylase
(B) Fumarylacetoacetate hydrolase
(C) Phenylalanine hydroxylase
(D) Tyrosine dehydrogenase
278. Which of the following is a substrate- specific enzyme?
(A) Hexokinase (B) Thiokinase
(C) Lactase (D) Aminopeptidase
279. Coenzymes combine with
(A) Proenzymes (B) Apoenzymes
(C) Holoenzymes (D) Antienzymes
280. Coenzymes are required in which of the following reactions?
(A) Oxidation-reduction
(B) Transamination
(C) Phosphorylation
(D) All of these
281. Which of the following coenzyme takes part in hydrogen transfer reactions?
(A) Tetrahydrofolate (B) Coenzyme A
(C) Coenzyme Q (D) Biotin
282. Which of the following coenzyme takes part in oxidation-reduction reactions?
(A) Pyridoxal phosphate
(B) Lipoic acid
(C) Thiamin diphosphate
(D) None of these
283. In conversion of glucose to glucose-6- phsophate, the coenzyme is
(A) Mg++
(B) ATP
(C) Both (A) and (B)
(D) None of these

284. A coenzyme required in transamination reactions is
(A) Coenzyme A (B) Coenzyme Q
(C) Biotin (D) Pyridoxal phosphate
285. Coenzyme A contains a vitamin which is
(A) Thiamin (B) Ascorbic acid
(C) Pantothenic acid (D) Niacinamide
286. Cobamides contain a vitamin which is
(A) Folic acid (B) Ascorbic acid
(C) Pantothenic acid (D) Vitamin B12
287. A coenzyme required in carboxylation reactions is
(A) Lipoic acid (B) Coenzyme A
(C) Biotin (D) All of these
288. Which of the following coenzyme takes part in tissue respiration?
(A) Coenzyme Q (B) Coenzyme A
(C) NADP (D) Cobamide
289. The enzyme hexokinase is a
(A) Hydrolase (B) Oxidoreductase
(C) Transferase (D) Ligase
290. Which of the following is a proteolytic enzyme?
(A) Pepsin (B) Trypsin
(C) Chymotrypsin (D) All of these
291. Enzymes which catalyse binding of two substrates by covalent bonds are known as
(A) Lyases (B) Hydrolases
(C) Ligases (D) Oxidoreductases
292. The induced fit model of enzyme action was proposed by
(A) Fischer (B) Koshland
(C) Mitchell (D) Markert
293. Allosteric inhibition is also known as
(A) Competitive inhibition
(B) Non-competitive inhibition
(C) Feedback inhibition
(D) None of these

294. An allosteric enzyme is generally inhibit- ed by
(A) Initial substrate of the pathway
(B) Substrate analogues
(C) Product of the reaction catalysed by allosteric enzyme
(D) Product of the pathway
295. When the velocity of an enzymatic reaction equals Vmax, substrate concentration is
(A) Half of Km (B) Equal to Km
(C) Twice the Km (D) Far above the Km
296. In Lineweaver-Burk plot, the y-intercept represents
(A) Vmax (B) Km
(C) Km (D) 1/Km
297. In competitive inhibition, the inhibitor
(A) Competes with the enzyme
(B) Irreversibly binds with the enzyme
(C) Binds with the substrate
(D) Competes with the substrate
298 Competitive inhibitors
(A) Decrease the Km (B) Decrease the Vmax
(C) Increase the K (D) Increase the V

302. Serum lactate dehydrogenase rises in
(A) Viral hepatitis
(B) Myocardial infarction
(C) Carcinomatosis
(D) All of these
303. Which of the following serum enzyme rises in myocardial infarction:
(A) Creatine kinase (B) GOT
(C) LDH (D) All of these
304. From the following myocardial infarction, the earliest serum enzyme to rise is
(A) Creatine Kinase (B) GOT
(C) GPT (D) LDH
305. Proenzymes:
(A) Chymotrysinogen (B) Pepsinogen
(C) Both (A) and (B) (D) None of these
306. Alkaline phosphatase is present in
(A) Liver (B) Bones
(C) Placenta (D) All of these
307. Which of the following isoenzyme of lactate dehydrogenase is raised in serum in myocardial infarction:

m max
299. Competitive inhibition can be relieved by

(A) LD

1

(B) LD

2

raising the
(A) Enzyme concentration
(B) Substrate concentration
(C) Inhibitor concentration
(D) None of these
300. Physostigmine is a competitive inhibitor of
(A) Xanthine oxidase
(B) Cholinesterase
(C) Carbonic anhydrase
(D) Monoamine oxidase
301. Carbonic anhydrase is competitively inhibited by
(A) Allopurinol (B) Acetazolamide
(C) Aminopterin (D) Neostigmine

(C) LD1 and LD2 (D) LD5
308. Enzymes which are always present in an organism are known as
(A) Inducible enzymes
(B) Constitutive enzymes
(C) Functional enzymes
(D) Apoenzymes
309. Inactive precursors of enzymes are known as
(A) Apoenzymes (B) Coenzymes
(C) Proenzymes (D) Holoenzymes
310. Whcih of the following is a proenzyme?
(A) Carboxypeptidase
(B) Aminopeptidase
(C) Chymotrypsin
(D) Pepsinogen

311. Allosteric enzymes regulate the formation of products by
(A) Feedback inhibition
(B) Non-competitive inhibition
(C) Competitive inhibition
(D) Repression-derepression
312 Regulation of some enzymes by covalent modification involves addition or removal of
(A) Acetate (B) Sulphate
(C) Phosphate (D) Coenzyme
313. Covalent modification of an enzyme generally requires a
(A) Hormone (B) cAMP
(C) Protein kinase (D) All of these
314. An inorganic ion required for the activity of an enzyme is known as
(A) Activator (B) Cofactor
(C) Coenzyme (D) None of these
315. The first enzyme found to have iso- enzymes was
(A) Alkaline Phosphatase
(B) Lactate dehydrogenase
(C) Acid Phosphatase
(D) Creatine kinase
316. Lactate dehydrogenase is located in
(A) Lysosomes (B) Mitochondria
(C) Cytosol (D) Microsomes
317. Lactate dehydrogenase is a
(A) Monomer (B) Dimer
(C) Tetramer (D) Hexamer
318. Ceruloplasmin is absent in
(A) Cirrhosis of liver (B) Wilson’s disease
(C) Menke’s disease (D) Copper deficiency
319. Ceruloplasmin oxidizes
(A) Copper (B) Iron
(C) Both (A) and (B) (D) None of these
320. Creatine kinase is present in all of the following except
(A) Liver (B) Myocardium
(C) Muscles (D) Brain

321. Alkaline phosphatase is present in
(A) Liver (B) Bones
(C) Intestinal mucosa (D) All of these
322. All of the following are zinc-containing enzymes except
(A) Acid Phosphatase
(B) Alkaline Phosphatase
(C) Carbonic anhydrase
(D) RNA polymerase
323. All of the following are iron-containing enzymes except
(A) Carbonic anhydrase
(B) Catalase
(C) Peroxidase
(D) Cytochrome oxidase
324. Biotin is a coenzyme for
(A) Pyruvate dehydrogenase
(B) Pyruvate carboxylase
(C) PEP carboxykinase
(D) Glutamate pyruvate transminase
325. Enzymes accelerate the rate of reactions by
(A) Increasing the equilibrium constant of reactions

(B) Increasing the energy of activation
(C) Decreasing the energy of activation
(D) Decreasing the free energy change of the reaction
326. Kinetics of an allosteric enzyme are explained by
(A) Michaelis-Menten equation
(B) Lineweaver-Burk plot
(C) Hill plot
(D) All of these
327. Covalent modification of an enzyme usually involves phosphorylation / dephosphorylation of
(A) Serine residue
(B) Proline residue
(C) Hydroxylysine residue
(D) Hydroxyproline residue

328. Vmax of an enzyme may be affected by
(A) pH
(B) Temperature
(C) Non-competitive inhibitors
(D) All of these
329. In enzyme assays, all the following are kept constant except
(A) Substrate concentration
(B) Enzyme concentration
(C) pH
(D) Temperature
330. If the substrate concentration is much below the km of the enzyme, the velocity of the reaction is
(A) Directly proportional to substrate concentration
(B) Not affected by enzyme concentration
(C) Nearly equal to Vmax
(D) Inversely proportional to substrate concentration
331. Enzymes requiring NAD as co-substrate can be assayed by measuring change in absorbance at
(A) 210 nm (B) 290 nm
(C) 340 nm (D) 365 nm
332. Different isoenzymes of an enzyme have the same
(A) Amino acid sequence
(B) Michaelis constant
(C) Catalytic activity
(D) All of these
333. From the pentapeptide, phe-ala-leu-lys- arg, phenylalanine residue is split off by
(A) Trypsin (B) Chymotrypsin
(C) Aminopeptidase (D) Carboxypeptidase
334. A high-energy phosphate among the following is
(A) Glucose-6-phosphate
(B) Glucose-1-phosphate
(C) 1, 3-Biphoglycerate
(D) All of these

335. The highest energy level is present amongst the following in
(A) 1, 3-Biphosphoglycerate
(B) Creatine phosphate
(C) Carbamoyl phosphate
(D) Phosphoenol pyruvate
336. Daily urinary urobilinogen excretion in adult men is
(A) 0–4 mg (B) 5–8 mg
(C) 9–12 mg (D) 13–20 mg
337. In obstructive jaundice, faecal urobilino- gen is
(A) Absent (B) Decreased
(C) Increased (D) Normal
338. Acetyl-CoA can be formed from
(A) Pyruvate (B) Fatty acids
(C) ketone bodies (D) All of these
339. Pyruvate is converted into acetyl-CoA by
(A) Decarboxylation
(B) Dehydrogenation
(C) Oxidative decarboxylation
(D) Oxidative deamination
340. Conversion of pyruvate into acetyl CoA is catalysed by
(A) Pyruvate dehydrogenase
(B) Didrolipoyl acetyl transferase
(C) Dihydrolipoyl dehydrogenase
(D) All the 3 acting in concert
341. Pyruvate dehydrogenase complex is located in
(A) Cytosol
(B) Lysosomes
(C) Mitochondria
(D) Endoplasmic reticulum
342. A flavoprotein in pyruvate dehydrogena- se complex is
(A) Pyruvate dehydrogenase
(B) Didrolipoyl acetyl transferase
(C) Dihydrolipoyl dehydrogenase
(D) None of these

343. Pyruvate dehydrogenase complex is regulated by
(A) Covalent modification
(B) Allosteric regulation
(C) Both (A) and (B)
(D) None of these
344. An allosteric inhibitor of pyruvate dehy- drogenase is
(A) Acetyl CoA (B) ATP
(C) NADH (D) Pyruvate
345. Ribozymes:
(A) RNA enzyme (B) Non-protein enzymes
(C) Catalyst function (D) All of these
346. In citric acid cycle, NAD is reduced in
(A) One reactions (B) Two reactions
(C) Three reactions (D) Four reactions
347. Among citric acid cycle enzymes, a flavo- protein is
(A) Malate
(B) Fumarase
(C) Succinate dehrogenase
(D) Isocitrate dehrogenase
348. In citric acid cycle, GDP is phosphorylated by
(A) Succinate dehydrogenase
(B) Aconitase
(C) Succinate thiokinase
(D) Fumarse
349. Malonate is an inhibitor of
(A) Malate dehydrogenase
(B) -Ketoglutarate dehydrogenase
(C) Succinate dehydrogenase
(D) Isocitrate dehydrogenase
350. Isocitrate dehydrogenase is allosterically inhibited by
(A) Oxalosuccinate (B) -Ketoglutarate
(C) ATP (D) NADH
351. All of the following are allosteric enzymes except
(A) Citrate synthetase
(B) a-Ketoglutarate dehdrogenase
(C) Succinate thiokinase
(D) Succinate dehydrogenase

352. All of the following are intermediates of citric acid cycle except
(A) Oxalosuccinate (B) Oxaloacetate
(C) Pyruvate (D) Fumarate
353. All of the following intermediates of citric acid cycle can be formed from amino acids except
(A) -Ketoglutarate (B) Fumarate
(C) Malate (D) Oxaloacetate
354. Glycolytic pathway is located in
(A) Mitochondria (B) Cytosol
(C) Microsomes (D) Nucleus
355. End product of aerobic glycolysis is
(A) Acetyl CoA (B) Lactate
(C) Pyruvate (D) CO2 and H2O
356. During fasting, glucose is phosphorylated mainly by
(A) Hexokinase (B) Glucokinase
(C) Both (A) and (B) (D) None of these
357. Glucokinase is found in
(A) Muscles (B) Brain
(C) Liver (D) All of these
358. In anaerobic glycolysis, energy yield from each molecule of glucose is
(A) 2 ATP equivalents (B) 8 ATP equivalents
(C) 30 ATP equivalents (D) 38 ATP equivalents
359. Which of the following is an allosteric enzyme?
(A) Phosphohexose isomerase
(B) Phosphotriose isomerase
(C) Lactate dehydrogenase
(D) Phosphofructokinase
360. Glycolysis is anaerobic in
(A) Liver (B) Brain
(C) Kidneys (D) Erythrocytes
361. Phosphofructokinase is allosterically inhibited by
(A) Fructose-1, 6-biphosphate
(B) Lactate
(C) Pyruvate
(D) Citrate

362. Glucose-6-phosphate is an allosteric inhibitor of
(A) Glucokinase
(B) Hexokinase
(C) Phosphohexose isomerase
(D) None of these
363. ATP is a co-substrate as well as an allos- teric inhibitor of
(A) Phosphofructokinase
(B) Hexokinase
(C) Glucokinase
(D) None of these
364. Complete oxidation of one molecule of glucose into CO2 and H2O yields
(A) 8 ATP equivalents
(B) 15 ATP equivalents
(C) 30 ATP equivalents
(D) 38 ATP equivalents
365. A unique by-product of glycolysis in erythrocytes is
(A) Lactate
(B) 1, 3-Biphosphoglycerate
(C) 2, 3-Biphosphoglycerate
(D) All of these
366. Which of the following enzymes incorpo- rates inorganic phosphate into the sub- strate?
(A) Phosphoglycerate kinase
(B) Glyceraldehyde-3-phosphate dehydrogenase
(C) Pyruvate kinase
(D) Enolase
367. Rapoport-Luebering cycle is located in
(A) Liver (B) Muscles
(C) Brain (D) Erythrocytes
368. Glycerol can enter glycolytic pathway via
(A) Dihydroxyacetone phosphate
(B) 1, 3-Biphospoglycerate
(C) 3-Phosphoglycerate
(D) 2-Phosphoglycerate
369. HMP shunt is present in
(A) Erythrocytes (B) Liver
(C) Testes (D) All of these

370. Glucose-6-phosphate dehydrogenase is induced by
(A) 6-Phosphogluconolactone
(B) Glucose-6-phosphate
(C) Ribose-5-phosphate
(D) Insulin
371. The decarboxylation reaction in HMP shunt is catalysed by
(A) Gluconolactone hydrolase
(B) 6-Phosphogluconate dehydrogenase
(C) 6-Phosphogluconate decarboxylase
(D) Transaldolase
372. The first pentose formed in HMP shunt is
(A) Ribose-5-phosphate (B) Ribulose-5-phosphate
(C) Xylose-5-phosphate (D) Xylulose-5-phosphate
373. The regulatory enzyme in HMP shunt is
(A) Glucose-6-phosphate dehydrogenase
(B) 6-Phosphogluconate dehydrogenase
(C) Both (A) and (B)
(D) None of these
374. The rate of HMP shunt reactions is
(A) Increased by Insulin
(B) Increased in diabetes mellitus
(C) Increased by glucagons
(D) Increased in starvation
375. Glycogenesis requires
(A) GTP (B) CTP
(C) UTP (D) None of these
376. Glycogen synthetase catalyses the formation of
(A) 1, 4-Glycosidic bonds
(B) 1, 6-Glycosidic bonds
(C) Both (A) and (B)
(D) None of these
377. Glycogenoloysis is increased by
(A) Glucagon (B) Insulin
(C) Epinephrine (D) cAMP
378. Hepatic glycogenoloysis is increased by
(A) Insulin (B) Glucagon
(C) Epinephrine (D) Glucocorticoids

379. Glycogen phosphorylase liberates the following from glycogen
(A) Glucose
(B) Glucose-6-phosphate
(C) Glucose-1-phosphate
(D) Maltose
380. After the action of phosphorylase, glyco- gen is converted into
(A) Amylopectin (B) dextrin
(C) Amylose (D) Maltose
381. Glucose-1-phosphate liberated from glycogen cannot be converted into free glucose in
(A) Liver (B) Kidneys
(C) Muscles (D) Brain
382. A coenzyme present in phosphorylase is
(A) NAD
(B) Pyridoxal phosphate
(C) Thiamin pyrophosphate
(D) Coenzyme A
383. If glucose-1-phosphate formed by glycogenoloysis in muscles is oxidized to CO2 and H2O, the energy yield will be
(A) 2 ATP equivalents (B) 3 ATP equivalents
(C) 4 ATP equivalents (D) 8 ATP equivalents
384. A molecule of phosphorylase kinase is made up of
(A) 4 subunits (B) 8 subunits
(C) 12 subunits (D) 16 subunits
385. Cyclic AMP binds to
(A) Catalytic subunits of protein kinase
(B) Regulatory subunits of protein kinase
(C) Catalytic subunits of phosphorylase kinase
(D) Regulatory subunits of phosphorylase kinase
386. Glucose is the only source of energy for
(A) Myocardium (B) Kidneys
(C) Erythrocytes (D) Thrombocytes
387. Glycerol-3-phosphate for the synthesis of triglycerides in adipose tissue is derived from
(A) Phosphatidic acid (B) Diacylglycerol
(C) Glycerol (D) Glucose

388. Gluconeogenesis does not occur in
(A) Brain (B) Kidneys
(C) Muscles (D) Liver
389. Glucose cannot be synthesized from
(A) Glycerol (B) Lactate
(C) Alanine (D) Leucine
390. Coenzyme for phosphoenolpyruvate carboxykinase is
(A) ATP (B) ADP
(C) GTP (D) GDP
391. Therapeutic enzymes:
(A) Streptokinase (B) Asparaginase
(C) Riboflavinase (D) Both (A) and (B)
392. A gluconeogenic enzyme among the following is
(A) Phosphofructokinase
(B) Pyruvate kinase
(C) Phosphoenol pyruvate carboxykinase
(D) Glucokinase
393. Glucose-6-phosphatase and PEP carboxy kinase are regulated by
(A) Covalent modification
(B) Allosteric regulation
(C) Induction and repression
(D) All of these
394. The maximum possible chain length of fatty acids formed in the pathway of de novo synthesis is
(A) 16 Carbon atoms (B) 18 Carbon atoms
(C) 20 Carbon atoms (D) 24 Carbon atoms
395. Acetyl CoA required for de novo synthesis of fatty acids is obtained from
(A) Breakdown of existing fatty acids
(B) Ketone bodies
(C) Acetate
(D) Pyruvate
396. Formation of acetyl CoA from pyruvate for de novo synthesis of fatty acids requires
(A) Pyruvate dehydrogenase complex
(B) Citrate synthetase
(C) ATP citrate lyase
(D) All of these

397. The major site for elongation of medium chain fatty acids is
(A) Mitochondria (B) Cytosol
(C) Microsomes (D) All of these
398. -oxidation of fatty acids is inhibited by
(A) NADPH (B) Acetyl CoA
(C) Malonyl CoA (D) None of these
399. The enzyme regulating extramitochondri- al fatty acid synthesis is
(A) Thioesterase
(B) Acetyl CoA carboxylase
(C) Acyl transferase
(D) Multi-enzyme complex
400. Acetyl CoA carboxylase is activated by
(A) Citrate (B) Insulin
(C) Both (A) and (B) (D) None of these
401. All the following statements about acetyl CoA carboxylase are true except:
(A) It is activated by citrate
(B) It is inhibited by palmitoyl CoA
(C) It can undergo covalent modification
(D) Its dephosphorylated form is inactive
402. All the following statements about acetyl CoA carboxylase are true except
(A) It is required for de novo synthesis of fatty acids
(B) It is required for mitochondrial elongation of fatty acids
(C) It is required for microsomal elongation of fatty acids
(D) Insulin converts its inactive form into its active form
403. Both Acyl carrier protein (ACP) of fatty acid synthetase and coenzyme (CoA) are
(A) Contain reactive phosphorylated
(B) Contain thymidine
(C) Contain phosphopantetheine reactive groups
(D) Contain cystine reactive groups
404. Which one of the following transfers acyl groups?
(A) Thiamine pyrophosphate
(B) Lipomide
(C) ATP
(D) NADH

405. Which one of the following cofactors must be utilized during the conversion of acetyl CoA to malonyl CoA?
(A) TPP (B) ACP
(C) NAD+ (D) Biotin
406. Which one of the following enzymes requires a coenzyme derived from the vitamin whose structure is shown below?
(A) Enoyl CoA hydratase
(B) Phosphofructokinase
(C) Glucose-6-phosphatase
(D) Glucose-6-phosphate dehydrogenase
407. Coenzymes derived from the vitamin shown below are required by enzymes involved in the synthesis of which of the following?
(A) ATP (B) UTP
(C) CTP (D) NADH
408. Coenzymes derived from the vitamin shown below are required by which of the following enzymes?
(A) Lactate dehydrogenase
(B) Glutamate dehydrogenase
(C) Pyruvate dehydrogenase
(D) Malate dehydrogenase
409. All the following are coenzymes except
(A) Ubiquinone
(B) CoA
(C) Pyruvate dehydrogenase
(D) Lipoic acid
410. Which of the following is not a cofactor?
(A) Mg (B) Iron
(C) Cu (D) Methylcobalamine
411. All the following compounds are members of the electron transport chain except
(A) Ubiquinone (B) Carnitine
(C) NAD (D) FAD
412. Thiamine is essential for
(A) Pyruvate dehydrogenase
(B) Isocitrate dehydrogenase
(C) Succinate dehydrogenase
(D) Acetyl CoA synthetase

413. Adenylate cyclase is activated by
(A) Insulin (B) Glucagon
(C) Prostaglandin E1 (D) Ca2+ ions
414. Maximum enzyme activity is observed at
(A) Acidic pH (B) Neutral pH
(C) Basic pH (D) Optimum pH
415. Which of the following is known as bone forming enzyme?
(A) Alkaline phosphatase
(B) Acid phosphatase
(C) Leucine aminopeptidase
(D) -glutamyl transpeptidase
416. Conversion of pepsinogen to pepsin is
(A) Intra molecular rearrangement
(B) Breaking of hydrogen bonds
(C) Covalent modification
(D) Polymerisation
417. Which of the following is not having an apoenzyme and coenzyme?
(A) Lactate dehydrogenase
(B) Succinate dehydrogenase
(C) Malate dehydrogenase
(D) Pepsin
418. Pyruvate dehydrogenase is a/an
(A) Isomerase (B) Lyase
(C) Ligase (D) Oxido reductase
419. Homogentisic oxidase is an
(A) Oxidase
(B) Monooxygenase
(C) Dioxygenase
(D) Anaerotic dehydrogenase
420. Isocitrate dehydrogenase can use
as a cofactor.
(A) NAD+ only (B) NADP+ only
(C) NAD+ or NADP+ (D) FMN and FAD
421. The rate of most enzyme catalysed reactions changes with pH. As the pH increases, this rate
(A) reaches a minimum, then increases
(B) reaches a maximum, then decreases
(C) increases
(D) decreases

422. A substrate for the enzyme aldolase is
(A) galactose-6-phosphate
(B) isocitric acid
(C) Glucose-1-phosphate
(D) Fructose 1, 6 diphosphate
423. Decarboxylation of -keto acids requires
(A) Thiamine pyrophosphate, FAD, NAD+
(B) Flavin mononucleotide
(C) NADP+
(D) NAD+ only
424. Coenzyme A contains the vitamin:
(A) Riboflavin (B) Pantothenic acid
(C) Pyridoxine (D) Thiamine
425. Which of the following is not a component of coenzyme A?
(A) Adenylic acid
(B) Pantothenic acid
(C)  -mercaptoethylamine
(D) Deoxyadenylic acid
426. Malic enzyme convers malic acid, in the presence of NADP+ to Pyruvic acid. This reaction is a/an
(A) Decarboxylation
(B) Decarboxylation and Dehydrogenation
(C) Dehydrogenation
(D) Oxidation
427. The following reaction is characteristic of what type of enzymes?
2H2O2  2H2O + O2
(A) Peroxides
(B) Catalase
(C) Dehydrogenase
(D) Copper containing oxidases
428. Of Which warburg’s yellow enzyme contains as a prosthetic group?
(A) Thiamine pyrophosphate
(B) Biotin
(C) NAD+
(D) Riboflavin-5-phosphate
429. Dehydrogenases utilize, as coenzymes, all of the following except
(A) NAD+ (B) NADP+
(C) FAD (D) FH4

430. Urea is produced physiologically by the action of the enzyme:
(A) Urease (B) Glutaminase
(C) Arginase (D) None of these
431. Urease is a
(A) Lyase (B) Ligase
(C) Isomerase (D) Hydrolase
432. Velocity maximum for an enzyme at half the substrate concentration gives
(A) The molecular weight of the enzyme
(B) Km value
(C) Isoelectric pH
(D) Pk value
433. Which of the following amino acid has been shown as one of the active site of phosphoglucomutase?
(A) Lysine (B) Tyrosine
(C) Serine (D) Histidine
434. The inhibition of succinate dehydro- genase by malonate by
(A) Competitive inhibition
(B) Non-competitive inhibition
(C) Uncompetitive inhibition
(D) Feedback inhibition
435. Cobamide coenzymes are
(A) Vitamin B1 (B) Riboflavin
(C) Pyridoxine (D) Vitamin B12
436. The isozyme CK-MB is specifically increased in the blood of patients who had
(A) Skeletal muscle disease
(B) Recent myocardial infarction
(C) Infective hepatitis
(D) Myxoedema
437. FAD containing enzyme, catalyzing formation of ,  unsaturated fatty acyl CoA derivative.
(A) Acyl CoA dehydrogenase
(B) Enoyl hydrase
(C) -OH acyl CoA dehydrogenase
(D) Thiolase

438. Immobilized enzymes:
(A) Potentiation of activity
(B) Presentation of activity
(C) Preparation of activity
(D) All of these
439. This catalyzes formation of CoA deriva- tives from fatty acid, CoA and ATP:
(A) Acyl CoA dehydrogenase
(B) Enoyl hydrase
(C) -OH acyl CoA dehydrogenase
(D) Thio kinase
440. Fructose 2, 3 bi phosphate is a powerful allosteric activator of
(A) Fructose 1, 6 diphosphatase
(B) Phosphofructokinase
(C) Hexokinase
(D) Fructokinase
441. ‘Clearing factor’ is
(A) Lipoprotein lipase
(B) Crotonase
(C) 7-dehydro cholesterol
(D) -sitosterol
442. Maltase attacks only
(A) -glucosides (B) -glucosides
(C) Starch (D) Dextrins
443. Pepsin is
(A) Exo-peptidase (B) Endo-peptidase
(C) Carboxy peptidase(D) Amino peptidase
444. An enzyme in saliva which hydrolyzes starch is
(A) Pepsinogen (B) Chymotrysin
(C) -Amylase (D) Malate
445. If a coenzyme is required in an enzyme reaction, the former usually has the function of
(A) Acting as an acceptor for one of the cleavage products of the substrate
(B) Enhancing the specificity of the apo enzyme
(C) Increasing the number of receptor sites of the apo enzyme
(D) Activating the substrate

446. The Michaehis-Menten hypothesis:
(A) Postulates the formation of an enzyme substrate complex
(B) Enables us to calculate the isoelectric point of an enzyme
(C) States that the rate of a chemical reaction may be independent of substrate concentration
(D) States that the reaction rate is proportional to substrate concentration
447. Schardinger’s enzyme is
(A) Lactate dehydrogenase
(B) Xanthine dehydrogenase
(C) Uric oxidase
(D) L amino acid dehydrogenase
448. Tryptophan pyrolase is currently known as
(A) Tryptophan deaminase
(B) Tryptophan dioxygenase
(C) Tryptophan mono oxygenase
(D) Tryptophan decarboxylase
449. An enzyme which brings about lysis of bacterial cell wall is
(A) Amylase (B) Lysozyme
(C) Trypsin (D) Lipase
450. Trypsin has no action on
(A) Hemoglobin (B) Albumin
(C) Histone (D) DNA
451. Multiple forms of the same enzymes are known as
(A) Zymogens (B) Isoenzymes
(C) Proenzymes (D) Pre-enzymes
452. In non-competitive enzyme action
(A) Vmax is increased
(B) Apparent km is increased
(C) Apparent km is decreased
(D) Concentration of active enzyme molecule is reduced
453. An allosteric enzyme influences the enzyme activity by
(A) Competiting for the catalytic site with the substrate

(B) Changing the specificity of the enzyme for the substrate
(C) Changing the conformation of the enzyme by binding to a site other than catalytic site
(D) Changing the nature of the products formed
454. Which of the following regulatory reactions involves a reversible covalent modification of an enzyme?
(A) Phosphorylation of serine OH on the enzyme
(B) Allosteric modulation
(C) Competitive inhibition
(D) Non-competitive inhibition
455. A competitive inhibitor of an enzyme has which of the following properties?
(A) It is frequently a feedback inhibitor
(B) It becomes covalently attached to an enzyme
(C) It decreases the Vmax
(D) It interferes with substrate binding to the enzyme
456. When [s] is equal to Km, which of the following conditions exist?
(A) Half the enzyme molecules are bound to substrate
(B) The velocity of the reaction is equal to Vmax
(C) The velocity of the reaction is independent of substrate concentration
(D) Enzyme is completely saturated with substrate
457. Which of the following statements about an enzyme exhibiting allosteric kinetics with cooperative interaction is false?
(A) A plot of V-Vk [s] has a sigmaidal shape
(B) An inhibitor may increase the apparent Km
(C) Line weaver Bnrk plot is useful for determining Km and Vmax
(D) Removal of allosteric inhibitor may result in hyperbolic V-S [s] plot
458. Pantothenic acid acts on
(A) NADP (B) NADPH
(C) FAD (D) CoA
459. Vitamin deficiency that causes fatty liver includes all except
(A) Vitamin E (B) Pyridoxine
(C) Retionic acid (D) Pantothenic acid

460. In which of the following types of enzymes an inducer is not required?
(A) Inhibited enzyme (B) Cooperative enzyme
(C) Allosteric enzyme (D) Constitutive enzyme
461. In which of the following types of enzyme water may be added to a C—C double bond without breaking the bond?
(A) Hydrolase (B) Hydratase
(C) Hydroxylase (D) Esterase
462. ‘Lock’ and ‘Key’ model of enzyme action proposed by Fisher implies that
(A) The active site is flexible and adjusts to substrate
(B) The active site requires removal of PO4 group
(C) The active site is complementary in shape to that of the substrate
(D) Substrates change conformation prior to active site interaction
463. In competitive inhibition of enzyme action
(A) The apparent Km is decreased
(B) The apparent Km is increased
(C) Vmax is decreased
(D) Apparent concentration of enzyme molecules decreased
464. In competitive inhibition which of the following kinetic effect is true ?
(A) Decreases both Km and Vmax
(B) Increases both Km and Vmax
(C) Decreases Km without affecting Vmax
(D) Increases Km without affecting Vmax
465. Enzymes increase the rates of reactions by
(A) Increasing the free energy of activation
(B) Decreasing the energy of activation
(C) Changing the equilibrium constant of the reaction
(D) Increasing the free energy change of the reaction
466. The most useful test for the diagnosis of acute hemorrhagic pancreatitis during the first few days is
(A) Urinary lipase test (B) Serum calcium
(C) Urinary amylase (D) Serum amylase

467. The best test for acute pancreatitis in the presence of mumps is
(A) A serological test for mumps
(B) Serum amylase
(C) Urinary amylase
(D) Serum lipase
468. The slow moving fraction of LDH is typically increased in pancreas with
(A) Cerebrovascular accidents
(B) Acute myocardial infarction
(C) Acute pancreatitis
(D) Acute viral hepatits
469. Which of the following enzyme typically elevated in alcoholism?
(A) Serum ALP
(B) Serum GOT
(C) Serum -GT
(D) Serum acid phosphatase
470. Patients with hepatocellular jaundice, as compared to those with purely obstruc- tive jaundice tend to have
(A) Lower serum ALP, LDH and AST activity
(B) Lower serum ALP, Higher LDH and AST activity
(C) Higher serum ALP, LDH and AST activity
(D) Higher serum ALP, Lower LDH and AST activity
471. If results of the serum bilirubin, serum ALP, LDH and AST determinations suggest obstructive jaundice, the best confirmatory test would be the estimation of
(A) Serum ALT
(B) Serum 5’ nucleotidase
(C) Serum Pseudo cholinesterase
(D) None of these
472. Which enzyme estimation will be helpful in differentiating the elevated serum ALP found in obstructive jaundice as well as bone disorders?
(A) Serum AST (B) Serum ALT
(C) Serum LDH (D) Serum -GT
473. Cardiac muscle contains which of the following CK osoenzyme?
(A) BB only (B) MM and BB only
(C) MM, BB and MB (D) MM and MB only

474. Liver and skeletol measle disorders are characterized by on disk proportionate increase in which of the LDH isoenzyme fraction?
(A) LDH-1 (B) LDH-1 and LDH-2
(C) LDH-3 and LDH-4 (D) LDH-2 and LDH-3
(E) LDH-5
475. On the third day following onset of acute myocardial infarction, which enzyme estimation will have the best predictive value?
(A) Serum AST (B) Serum CK
(C) Serum ALT (D) Serum LDH
476. Serum AST activity is not characteristically elevated as the result of
(A) Myocardial infarction
(B) Passive congestion of liver
(C) Muscular dystrophies
(D) Peptic ulcer
477. On which day following acute myocardial infarction the estimation of serum AST will be of greatest significance?
(A) First day (B) Second day
(C) Third day (D) Fourth day
478. In which diseases of the following organs, isoenzymes LDH-1 and LDH-2 will be released in plasma?
(A) Kidney, R.B.C and Liver
(B) Heart, Kidney and R.B.C
(C) Heart, Kidney and Liver
(D) Heart, Lungs and Brain
479. Plasma non-functional enzymes are
(A) totally absent
(B) low concentration in plastic
(C) important for diagnosis of several disease
(D) All of these
480. Pyruvate dehydrogenase contains all except
(A) Biotin (B) NAD
(C) FAD (D) CoA
481. An increase in LDH-5 enzyme is seen in the following except
(A) Acute hepatitis (B) Muscular distrophies
(C) Breast carcinoma (D) Pulmonary embolism

482. Diastase can be used for the hydrolysis can be used for the hydrolysis of
(A) Sucrose (B) Starch
(C) Cellulose (D) Maltose
483. Which of the following statements is true?
(A) Enzymes have names ending ase
(B) Enzymes are highly specific in their action
(C) Enzymes are living organisms
(D) Enzymes get activated on heating
484. Enzymes activity is controlled by
(A) pH of the solution
(B) Temperature
(C) Concentration of the enzyme
(D) Concentration of the substrate
(E) All of these
485. Which of the following is not true regard- ing enzymes?
(A) They catalyze only a particular type of reaction
(B) They remain active even after separation from the source
(C) They are destroyed after the completion of the reaction they catalyse
(D) They are irreversibly destroyed at high temperature
(E) Their activity depends on the pH of the solution
486 The number of enzymes known is about
(A) 10,000 (B) 100
(C) 50 (D) 26
487. Nicotine present in tobacco is a/an
(A) Alkaloid (B) Terpene
(C) Steroid (D) Protein
488. The poisonous alkaloid present in the oil of hemlock is
(A) Cocaine (B) Nicotine
(C) Quinine (D) Morphine
489. Alkaloids are usually purified by extrac- tion with
(A) Ether (B) Dil HCl
(C) NaOH (D) Chloroform

490. The number of N-MC groups in alkaloids is best estimate with the help of
(A) HI (B) H2SO4
(C) (CH3CO)2 CO (D) CH3 Mg I
491. A competitive inhibitor of an enzyme
(A) Increases Km without affecting Vmax
(B) Decreases Km without affecting Vmax
(C) Increases Vmax without affecting Km
(D) Decreases both Vmax and Km
492. The Michaelis constant, Km is
(A) Numerically equal to ½ Vmax
(B) Dependent on the enzyme concentration
(C) Independent of pH
(D) Numerically equal to the substrate concen- tration that gives half maximal velocity
493. The rate of an enzyme catalyzed reaction was measured using several substrate concentrations that were much lower than Km, the dependence of reaction velocity on substrate concentration can best be described as
(A) Independent of enzyme concentration
(B) A constant fraction of Vmax
(C) Equal to Km
(D) Proportional to the substrate concentration
494. The presence of a non competitive inhibitor
(A) Leads to both an increase in the Vmax of a reaction and an increase in Km
(B) Leads to a decrease in the observed Vmax
(C) Leads to a decrease in Km and Vmax
(D) Leads to an increase in Km without affecting Vmax
495. Which one of the following statements is not characteristic of allosteric enzymes?
(A) They frequently catalyze a committed step early in a metabolic pathway
(B) They are often composed of subunits
(C) They follow Michaelis-Menten kinetics
(D) They frequently show cooperativity for substrate binding
496. The abnormal isoenzyme need not
(A) Be an oxidoreductase
(B) Have any coenzyme
(C) Require ATP

(D) Be localized intracellularly
(E) Be a catalyst
497. LDH assays are most useful in diagnosing diseases of the
(A) Heart (B) Pancreas
(C) Brain (D) Kidney
498. The chemical forces that bind most coenzymes and substrates to enzymes such as LDH are
(A) Hydrogen bonds (B) Peptide bonds
(C) Coordinate bonds (D) Covalent bonds
499. How many different proteins may be present in normal LDH?
(A) One (B) Two
(C) Three (D) Four
500. All the isoenzymes function with the coenzyme:
(A) NADP+ (B) FAD
(C) Lipoate (D) NAD+
501. ‘Lock’ and ‘Key’ theory was proposed by
(A) Sorenson (B) Fischer
(C) Mehler (D) Sanger
502. Which of the following forms part of a coenzyme?
(A) Zn2+ (B) Lipase
(C) Vitamin B2 (D) Lysine
503. The shape of an enzyme and conse- quently its activity can be reversibly altered from moment to moment by
(A) Heat (B) Amino acid substrate
(C) Allosteric subunits (D) Sulfur substitutions
504. Which one of the following regulatory actions involves a reversible covalent modification of the enzyme?
(A) Phosphorylation of ser-OH on the enzyme
(B) Allosteric modulation
(C) Competitive inhibition
(D) Non-competitive inhibition
505. An enzyme is a
(A) Carbohydrate (B) Lipid
(C) Protein (D) Nucleic acid

506. An enzyme promotes a chemical reaction by
(A) Lowering the energy of activation
(B) Causing the release of heat which acts as a primer
(C) Increasing molecular motion
(D) Changing the free energy difference between substrate and product
507. In most metabolic pathways, all needed enzymes are arranged together in a multienzyme complex within a
(A) Solution of ATP
(B) Membrane
(C) Quanternary protein
(D) Coenzyme
508. An enzyme catalyzes the conversion of an aldose sugar to a ketose sugar would be classified as one of the
(A) Transferases (B) Isomerases
(C) Oxido reductases (D) Hydrolases
509. The function of an enzyme is to
(A) Cause chemical reactions that would not otherwise take place
(B) Change the rates of chemical reactions
(C) Control the equilibrium points of reactions
(D) Change the directions of reactions
510. In which of the following types of enzymes, water may be added to a C—C double bond without breaking the bond?
(A) Hydrolase (B) Hydratase
(C) Hydroxylase (D) Oxygenase
511. Enzymes increases the rate of reactions by
(A) Increasing the free energy of activation
(B) Decreasing the energy of activation
(C) Changing the equilibrium constant of the reaction
(D) Increasing the free energy change of the reaction
512. The active site of an enzyme is formed by a few of the enzymes:
(A) R groups of the amino acids
(B) Amino groups of the amino acids

(C) Carboxyl group of the amino acids
(D) Exposed sulfur bonds
513. Allosteric enzymes contain
(A) Multiple subunits (B) Single chain
(C) Two chains (D) Three chains
514. Isoenzymes of lactate dehydrogenase are useful for the diagnosis of
(A) Heart disease (B) Kidney disease
(C) Liver disease (D) Both (A) and (C)
515. IUB had divided enzymes into how many classes?
(A) 6 (B) 5
(C) 8 (D) 4
516. The first enzyme isolated, purified and crystallied from Jack bean (Canavalia) by summer in 1926 was
(A) Urease (B) Insulin
(C) Ribonuclease (D) Zymase
517. Who suggested that enzymes are protein- aceous?
(A) Buchner (B) Kuhne
(C) Sumner (D) Pasteur
518. Feedback inhibition of enzyme action is affected by
(A) Enzyme (B) Substrate
(C) End products (D) None of these
519. The enzyme that converts glucose to glucose-6-phosphate is
(A) Phosphatase (B) Hexokinase
(C) Phosphorylase (D) Glucose synthetase
520. Enzymes are required in traces because they
(A) Have high turnover number
(B) Remain unused at the end of reaction and are re used
(C) Show cascade effect
(D) All correct
521. An organic substance bound to an enzyme and essential for the activity of enzyme is called
(A) Holoenzyme (B) Apoenzyme
(C) Coenzyme (D) Isoenzyme

522. Enzyme catalysed reactions occur in
(A) Pico seconds (B) Micro seconds
(C) Milli seconds (D) None of these
523. An enzyme can accelerate a reaction up to
(A) 1010 times (B) 101 times
(C) 10100 times (D) 10 times
524. In plants, enzymes occur in
(A) Flowers only (B) Leaves only
(C) All living cells (D) Storage organs only
525. Zymogen is a
(A) Vitamin (B) Enzyme precursor
(C) Modulator (D) Hormone
526. Cofactor (Prosthetic group) is a part of holoenzyme, it is
(A) Inorganic part loosely attached
(B) Accessory non-protein substance attached firmly
(C) Organic part attached loosely
(D) None of these
527. A protein having both structural and enzymatic traits is
(A) Myosin (B) Collagen
(C) Trypsin (D) Actin
528. Enzymes are different from catalysts in
(A) Being proteinaceous
(B) Not used up in reaction
(C) Functional at high temperature
(D) Having high rate of diffusion
529. Enzymes, vitamins and hormones are common in
(A) Being proteinaceous
(B) Being synthesized in the body of organisms
(C) Enhancing oxidative metabolism
(D) Regulating metabolism
530. Dry seeds endure higher temperature than germinating seeds as
(A) Hydration is essential for making enzymes sensitive to temperature
(B) Dry seeds have a hard covering

(C) Dry seeds have more reserve food
(D) Seedlings are tender
531. Coenzymes FMN and FAD are derived from vitamin
(A) C (B) B6
(C) B1 (D) B2
532. Template/lock and key theory of enzyme action is supported by
(A) Enzymes speed up reaction
(B) Enzymes occur in living beings and speed up certain reactions
(C) Enzymes determine the direction of reaction
(D) Compounds similar to substrate inhibit enzyme activity
533. Combination of apoenzyme and coenzyme produces
(A) Prosthetic group
(B) Holoenzyme
(C) Enzyme substrate complex
(D) Enzyme product complex
534. Enzyme inhibition caused by a substance resembling substrate molecule is
(A) Competitive inhibition
(B) Non-competitive inhibition
(C) Feedback inhibition
(D) Allosteric inhibition
535. An enzyme brings about
(A) Decrease in reaction time
(B) Increase in reaction time
(C) Increase in activation energy
(D) Reduction in activation energy
536. Feedback inhibition of enzyme is influen- ced by
(A) Enzyme (B) External factors
(C) End product (D) Substrate
537. Coenzyme is
(A) Often a vitamin (B) Always an inorganic compound
(C) Always a protein (D) Often a metal

538. Genetic engineering requires enzyme:
(A) DNA ase
(B) Amylase
(C) Lipase
(D) Restriction endonuclease
539. Which is not true about inorganic cata- lysts and enzymes?
(A) They are specific
(B) Inorganic catalysts require specific not needed by enzymes
(C) They are sensitive to pH
(D) They speed up the rate of chemical reaction
540. Key and lock hypothesis of enzyme action was given by
(A) Fischer (B) Koshland
(C) Buchner (D) Kuhne
541. An example of feedback inhibition is
(A) Allosteric inhibition of hexokinase by glucose- 6-phosphate
(B) Cyanide action on cytochrome
(C) Sulpha drug on folic acid synthesizer bacteria

(D) Reaction between succinic dehydrogenase and succinic acid
542. Feedback term refers to
(A) Effect of substrate on rate of enzymatic reaction
(B) Effect of end product on rate reaction
(C) Effect of enzyme concentration on rate of reaction
(D) Effect of external compound on rate of reaction
543. Allosteric inhibition
(A) Makes active site unifit for substrate
(B) Controls excess formation and end product
(C) Both (A) and (B)
(D) None of these
544. The ratio of enzyme to substrate mole- cules can be as low as
(A) 1 : 100,000 (B) 1 : 500,000
(C) 1 : 10,000 (D) 1 : 1,000

545. Vitamin B2 is component of coenzyme:
(A) Pyridoxal phosphate
(B) TPP
(C) NAD
(D) FMN/FAD
546. Km value of enzyme is substrate concen- tration at
(A) ½ Vmax (B) 2 Vmax
(C) ½ Vmax (D) 4 Vmax
547. Part of enzyme which combines with non- protein part to form functional enzyme is
(A) Apoenzyme (B) Coenzyme
(C) Prosthetic group (D) None of these
548. Who got Nobel Prize in 1978 for working on enzymes?
(A) Koshland (B) Arber and Nathans
(C) Nass and Nass (D) H.G. Khorana
549. Site of enzyme synthesis in a cell is
(A) Ribosomes (B) RER
(C) Golgi bodies (D) All of these
550. The fruit when kept is open, tastes bitter after 2 hours because of
(A) Loss of water from juice
(B) Decreased concentration of fructose in juice
(C) Fermentation by yeast
(D) Contamination by bacterial enzymes
551. Hexokinase (Glucose + ATP  Glucose-6– P + ADP) belongs to the category:
(A) Transferases (B) Lysases
(C) Oxidoreductases (D) Isomerases
552. Which enzyme is concerned with transfer of electrons?
(A) Desmolase (B) Hydrolase
(C) Dehydrogenase (D) Transaminase
553. The best example of extracellular enzymes (exoenzyme) is
(A) Nucleases
(B) Digestive enzymes
(C) Succinic dehydrogenase
(D) None of these

554. Which mineral element controls the activity of Nitrate reductase ?
(A) Fe (B) Mo
(C) Zn (D) Ca
555. Name the enzyme that acts both as carboxylase at one time and oxygenase at another time.
(A) PEP carboxylase
(B) RuBP carboxylase
(C) Carbonic anyhdrase
(D) None of these
556. A metabolic pathways is a
(A) Route taken by chemicals
(B) Sequence of enzyme facilitated chemical reactions
(C) Route taken by an enzyme from one reaction to another
(D) Sequence of origin of organic molecules
557. The energy required to start an enzymatic reaction is called
(A) Chemical energy (B) Metabolic energy
(C) Activation energy (D) Potential energy
558. Out of the total enzymes present in a cell, a mitochondrion alone has
(A) 4% (B) 70%
(C) 95% (D) 50%
559. Creatine phosphokinase isoenzyme is a marker for
(A) Kidney disease
(B) Liver disease
(C) Myocardial infarction
(D) None of these
560. Which inactivates an enzyme by occu- pying its active site?
(A) Competitive inhibitor
(B) Allosteric inhibitor
(C) Non-competitive inhibitor
(D) All of these
561. Which one is coenzyme?
(A) ATP (B) Vitamin B and C
(C) CoQ and CoA (D) All of these
562. The active site of an enzyme is formed by
(A) R group of amino acids

(B) NH2 group of amino acids
(C) CO group of amino acids
(D) Sulphur bonds which are exposed
563. Carbonic anhydrase enzyme has maxi- mum turn over number (36 million). Min- imum turn over number for an enzyme:
(A) DNA polymerase
(B) Lysozyme
(C) Penicillase
(D) Lactase dehydrogenase
564. In cell, digestive enzymes are found mainly in
(A) Vacuoles (B) Lysosomes
(C) Ribosomes (D) Lomasomes
565. Substrate concentration at which an enzyme attains half its maximum velocity is
(A) Threshold value
(B) Michaelis-Menton constant
(C) Concentration level
(D) None of these
566. Which enzyme hydrolyses starch?
(A) Invertase (B) Maltase
(C) Sucrase (D) Diastase
567. Enzymes functional in cell or mitochondria are
(A) Endoenzymes (B) Exoenzymes
(C) Apoenzymes (D) Holoenzymes
568. The enzymes present in the membrane of mitochondria are
(A) Flavoproteins and cytochromes
(B) Fumarase and lipase
(C) Enolase and catalase
(D) Hexokinase and zymase
569. A mitochondrial marker enzyme is
(A) Aldolase
(B) Amylase
(C) Succinic dehydrogenase
(D) Pyruvate dehydrogenase

570. The enzyme used in polymerase chain reaction (PCR) is
(A) Taq polymerase (B) RNA polymerase
(C) Ribonuclease (D) Endonuclease

579. Transaminase activity needs the Co- enzyme:
(A) ATP (B) B6-PO4
(C) FADT (D) NAD+

571. Which of the following is a microsomal en- zyme inducer? 580. The biosynthesis of urea occurs mainly in the liver:
(A) Indomethacin (B) Clofibrate (A) Cytosol (B) Mitochondria
(C) Tolbutamide (D) Glutethamide (C) Microsomes (D) Nuclei
572. Identify the correct molecule which controls the biosynthesis of proteins in 581. Bile salts make emulsification with fat for the action of

living organisms.
(A) DNA (B) RNA
(C) Purines (D) Pyrimidines
573. The tear secretion contains an antibac- terial enzyme known as
(A) Zymase (B) Diastase
(C) Lysozyme (D) Lipase
574. Identify one of the canbonic anhydrase inhibitor that inhibit only luminal carbonic anhydrase enzyme.
(A) Methazolamide (B) Acetazolamide
(C) Dichlorphenamide (D) Benzolamide
575. Group transferring Co-enzyme is
(A) CoA (B) NAD+
(C) NADP+ (D) FAD+
576. The co-enzyme containing an automatic hetero ring in the structure is
(A) Biotin (B) TPP
(C) Sugar Phosphate (D) Co-enzyme
577. The example of hydrogen transferring Co-enzyme is:
(A) B6-PO4 (B) NADP+
(C) TPP (D) ATP
578. Enzyme catalyzed hydrolysis of proteins produces amino acid of the form
(A) D (B) DL
(C) L (D) Racemic

(A) Amylose (B) Lipase
(C) Pepsin (D) Trypsin
582. All of the following compounds are intermediates of TCA cycle except
(A) Maleate (B) Pyruvate
(C) Oxaloacetate (D) Fumarate
583. In conversion of lactic acid to glucose, three reactions of glycolytic pathway are circumvented, which of the following enzymes do not participate?
(A) Pyruvate carboxylase
(B) Phosphoenol pyruvate carboxy kinase
(C) Pyruvate kinase
(D) Glucose-6-phosphatase
584. In the normal resting state of human most of the blood glucose burnt as fuel is consumed by
(A) Liver (B) Brain
(C) Adipose tissue (D) Muscles
585. A regulator of the enzyme glucogen synthase is
(A) Citric Acid (B) Pyruvate
(C) Glucose-6-PO4 (D) GTP
586. A specific inhibitor for succinate dehydro- genase is
(A) Arsenite (B) Malonate
(C) Citrate (D) Fluoride