OCET-2012 - Punjab University Question Paper
Question Booklet Series : A Sr. No. :
Important : Please consult your Admit Card / Roll No. Slip before filling your Roll Number on the Test Booklet and Answer Sheet.
Roll No.
O.M.R. Answer Sheet Serial No.
Signature of the Candidate :
Subject : M.Sc. (Hons. School)-Biochemistry
Time : 90 minutes Number of Questions : 75 Maximum Marks : 75
DO NOT OPEN THE SEAL ON THE BOOKLET UNTIL ASKED TO DO SO
INSTRUCTIONS
1. Write your Roll No. on the Question Booklet and also on the OMR Answer Sheet in the space provided and nowhere else.
2. Enter the Subject and Series Code of Question Booklet on the OMR Answer Sheet. Darken the corresponding bubble with Black Ball Point /Black Gel pen.
3. Do not make any identification mark on the Answer Sheet or Question Booklet.
4. To open the Question Booklet remove the paper seal (s) gently when asked to do so.
5. Please check that this Question Booklet contains 75 questions. In case of any discrepancy, inform the Assistant Superintendent within 10 minutes of the start of test.
6. Each question has four alternative answers (A, B, C, D) of which only one is correct. For each question, darken only one bubble (A or B or C or D), whichever you think is the correct answer, on the Answer Sheet with Black Ball Point / Black Gel pen.
7. If you do not want to answer a question, leave all the bubbles corresponding to that question blank in the Answer Sheet. No marks will be deducted in such cases.
8. Darken the bubbles in the OMR Answer Sheet according to the Serial No. of the questions given in the Question Booklet.
9. Negative marking will be adopted for evaluation i.e., 1/4th of the marks of the question will be deducted for each wrong answer. A wrong answer means incorrect answer or wrong filling of bubble.
10. For calculations, use of simple log tables is permitted. Borrowing of log tables and any other material is not allowed.
11. For rough work only the sheets marked “Rough Work” at the end of the Question Booklet be used.
12. The Answer Sheet is designed for computer evaluation. Therefore, if you do not follow the instructions given on the Answer Sheet, it may make evaluation by the computer difficult. Any esultant loss to the candidate on the above account, i.e., not following the instructions completely, shall be of the candidate only.
13. After the test, hand over the Question Booklet and the Answer Sheet to the Assistant Superintendent on duty.
14. In no case the Answer Sheet, the Question Booklet, or its part or any material copied/noted from this Booklet is to be taken out of the examination hall. Any candidate found doing so, would be expelled from the examination.
15. A candidate who creates disturbance of any kind or changes his/her seat or is found in possession of any paper possibly of any assistance or found giving or receiving assistance or found using any other unfair means during the examination will be expelled from the examination by the Centre Superintendent / Observer whose decision shall be final.
16. Telecommunication equipment such as pager, cellular phone, wireless, scanner, etc., is not
permitted inside the examination hall. Use of calculators is not allowed.
M.Sc.(Hons.School)-Biochemistry/A
1. Which of the following amino acids has not a charged side chain at physiologic pH ?
(A) Aspartic acid (B) Lysine
(C) Glutamic acid (D) Asparagine
2. Glutamine has :
(A) three titratable groups
(B) an amide group
(C) an acidic amino acid
(D) a side chain that cannot form hydrogen bonds in proteins
3. The GSH has following amino acids :
(A) Gln-Cys-Leu (B) Glu-Cys-Gly
(C) Asp-Ala-Gly (D) Glu-Asp-Gly
4. Edman degradation uses which reagent for sequencing a polypeptide ?
(A) Fluorotrinitrobenzene (B) Sanger's reagent
(C) Phenylisothiocyanate (D) Dansyl chloride
5. Which one is odd one out ?
(A) Eadie-Hofstee (B) Shine-Dalgarno
(C) Lineweaver-Burk (D) Michaelis-Menten
6. Which of the following is not part of protein sequencing ?
(A) Edman degradation (B) Amadori rearrangements
(C) HPLC (D) FAB-MS
7. A competitive inhibitor of an enzyme :
(A) increases Km without affecting Vm (B) decreases Km without affecting Vm
(C) increases Vm without affecting Km (D) decreases Vm without affecting Km
8. Restriction endonucleases as per EC numbering belong to class :
(A) 1 (B) 2
(C) 3 (D) 6
9. Large soluble proteins with many disulfide linked chains released into serum are :
(A) Albumins (B) Haemoglobin
(C) Collagen (D) IgG
10. Which of the following is most abundant protein secreted by fibroblasts ?
(A) Keratin (B) Collagen
(C) IgG (D) Alumin
11. What is the maximum insert size (Kb) of bacterial Plasmid ?
(A) 6–12 (B) 25–40
(C) 45–100 (D) 15–50
12. Fructosuria is the result of :
(A) a deficiency of phosphofructokinase (B) a deficiency of liver fructokinase
(C) elevated levels of liver aldolase B (D) a deficiency of liver hexokinase
13. Which one of the following is the major end product of protein-Nitrogen metabolism ?
(A) Glycine (B) Uric acid
(C) Urea (D) Arginine
14. A hereditary childhood disease, galactosemia, is characterized by a :
(A) high level of liver UDP-galactose
(B) lack of glucose 1-phosphate
(C) very low galactose 1-phosphate uridyltransferase activity in liver
(D) lack of galactokinase
15. Biosynthesis of glucuronic acid requires the :
(A) oxidation of UDP-glucose (B) oxidation of glucose 6-phosphate
(C) oxidation of 6-phosphogluconate (D) reduction of sorbitol
16. In Tay-Sachs disease lead to accumulation of GM2 due to :
(A) Hexosaminidase (B) Galactosidase
(C) Sulfatase (D) Neuranindase
17. Muscle glycogen cannot contribute directly to blood glucose levels because :
(A) muscle glycogen cannot be converted to glucose 6-phosphate
(B) muscle lacks glucose 6-phosphate phosphatase
(C) muscle contains no glucokinase
(D) muscle contains no glycogen phosphorylase
18. In the muscle, a sudden elevation of the Ca++ concentration will cause :
(A) activation of cyclic AMP-dependent protein kinase
(B) dissociation of cyclic AMP-dependent protein kinase into catalytic and regulatory subunits
(C) conversion of glycogen phosphorylase b to phosphorylase a
(D) conversion of cyclic AMP to AMP by phosphodiesterase
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 5 [Turn over
19. Mucopolysaccharidoses are inherited storage diseases. They are caused by :
(A) an increased rate of synthesis of proteoglycans
(B) the synthesis of polysaccharides with an altered structure
(C) defects in the degradation of proteoglycans
(D) the synthesis of abnormally small amounts of protein cores
20. Which one of the following is NOT a common feature of the carbohydrate structure in Nlinked and O-linked glycoproteins ?
(A) They may contain N-acetylneuraminic acid
(B) They may contain glucose
(C) Their degradation in vivo involves action of lysosomal enzymes
(D) Their synthesis involves participation of a lipid carrier
21. An uncoupler of oxidative phosphorylation such as dinitrophenol :
(A) inhibits respiration and ATP synthesis
(B) allows electron transport to proceed without ATP synthesis
(C) inhibits respiration without impairment of ATP synthesis
(D) specifically inhibits cytochrome b
22. The rate of glycolysis is controlled in part by inhibition of :
(A) NADH reductase (B) phosphofructokinase by citrate
(C) phosphofructokinase II (D) glucokinase by ATP
23. In pyruvate kinase deficiency, hemolysis of red cells occurs primarily because of increased intracellular levels of :
(A) lactate (B) pyruvate
(C) the ratio of ADP to ATP (D) 2,3-diphosphoglycerate
24. Which one of the following reactions is unique to gluconeogenesis ?
(A) Lactate →pyruvate
(B) Phosphoenolpyruvate (PEP)→pyruvate
(C) Oxaloacetate→phosphoenolypyruvate
(D) Glucose 6-phosphate→fructose 6-phosphate
25. Which of the following enzymic activities would you expect to be decreased in thiamine deficiency ?
(A) Pyruvate carboxylase (B) Isocitrate dehydrogenase
(C) Fumarase (D) -Ketoglutarate dehydrogenase
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 6
26. Which is the major phospholipid of eukaryotic cell membranes ?
(A) Cardiolipin (B) Phosphatidylcholine
(C) Cholesterol (D) Shingolipids
27. Substances that play a direct role in the synthesis of palmitate by the fatty acid synthetase complex include :
(A) covalently bound phosphopantetheine (B) covalently bound lipoic acid
(C) malonyl CoA (D) both (A) and (C)
28. In humans, carnitine :
(A) stimulates the activity of acetyl CoA carboxylase
(B) is important for fatty acid oxidation
(C) inhibits the formation of triacylglycerol
(D) none of these
29. In the major pathway by which liver produces ketone bodies, the immediate precursor of acetoacetate is :
(A) acetoacetyl CoA (B) -hydroxybutyrate
(C) 3-hydroxy-3-methylglutaryl CoA (D) two molecules of acetyl CoA
30. Hydrolysis of a mixture of phosphoglycerides will not yield which of the following compounds ?
(A) Choline (B) Glycerol
(C) Phosphate (D) Tryptophan
31. To be defined as a ganglioside, a lipid substance isolated from nerve tissue must contain in its structure :
(A) N-acetylneuraminic acid (NANA) hexoses, sphingosine, long chain fatty acids
(B) NANA, a hexose, a fatty acid, sphingosine, phosphorylcholine
(C) NANA, sphingosine, ethanolamine
(D) All of the above
32. Animals fed a high cholesterol diet exhibit decreased cholesterol synthesis by liver because of the inhibition of which one of the following enzymes ?
(A) 3-Hydroxy-3-methyl glutaryl CoA (HMG CoA) synthetase
(B) HMG CoA reductase
(C) Mevalonate kinase
(D) HMG CoA lyase
33. The lipoprotein particles that have the highest percent concentration of triacylglycerol are :
(A) the chylomicrons (B) the VLDL
(C) the LDL (D) the HDL
34. Chymotrypsin acts :
(A) in the stomach on peptide bonds formed by the amino acid glycine
(B) in the intestinal mucosa on carboxy-terminal amino acids in proteins and peptides
(C) in the intestine on peptide bonds formed by the amino acids arginine or aspartate
(D) in the intestine on peptide bonds formed by amino acids with aromatic side-chains
35. -Aminolevulinic acid synthase activity :
(A) is frequently increased in individuals treated with drugs, such as the barbiturate phenobarbital
(B) catalyses a rate-limiting reaction in porphyrin biosynthesis
(C) requires the cofactor pyridoxal phosphate
(D) all of the above
36. The catabolism of heme :
(A) occurs in the cells of the reticuloendothelial system
(B) involves the oxidative cleavage of the porphyrin ring
(C) results in the liberation of carbon monoxide
(D) all of the above
37. Insulin does all of the following EXCEPT :
(A) enhance glucose transport into muscles
(B) enhance glycogen formation of liver
(C) decrease lipolysis in adipose tissue
(D) enhance gluconeogenesis in liver
38. Ingestion of a metal consisting exclusively of protein would result in which of the following ?
(A) An increased release of insulin
(B) Hypoglycemia
(C) A decreased release of glucagon
(D) Ketoacidosis caused by the metabolism of ketogenic amino acids
39. Increased formation of ketone bodies during starvation is due to :
(A) mobilization of high-density lipoproteins
(B) formation of acetyl CoA in amounts that exceed the oxidative capacity of the liver
(C) decreased levels of free fatty acids in the liver
(D) a decreased mobilization of triacylglycerols from adipose tissue
40. The abbreviation "W" stands for which of the following amino acids ?
(A) Proline (B) Phenylalanine
(C) Tyrosine (D) Tryptophan
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 8
41. The coenzyme required in oxidative decarboxylation is :
(A) biotin (B) vitamin B12
(C) ascorbic acid (D) thiamine pyrophosphate
42. Which of the following reactions involves the participation of thiamine ?
(A) Lactate→pyruvate
(B) -ketoglutarate→succinyl CoA
(C) Acetyl CoA→malonyl CoA
(D) none of the above
43. Vitamin D :
(A) increases absorption of calcium from the intestine
(B) is not required in the diet of individuals exposed to sunlight
(C) is not really a vitamin because the active form, 1,25-dihydroxycholecalciferol can be synthesized in humans
(D) all of the above
44. -Tocopherol :
(A) functions primarily as an antioxidant
(B) deficiency is commonly found in adults
(C) requirements increase with the amount of polyunsaturated fatty acids in the diet
(D) both (A) and (C)
45. Complete acid hydrolysis of nucleic acids yields all of the following EXCEPT :
(A) phosphoric acid (B) purines
(C) pentoses (D) adenosine
46. Histones :
(A) are basic protein rich in lysine or arginine, or both
(B) are bound covalently to DNA
(C) have relatively high molecular weights (2,00,000 daltons or higher)
(D) are identical to protamines
47. The formation of uric acid from purines is catalysed by :
(A) adenylate deaminase (B) uricase
(C) urease (D) xanthine oxidase
48. The committed step in pyrimidine biosynthesis :
(A) provides a classic example of positive feedback control
(B) results in the formation of dihydroorotic acid
(C) is the formation of N-carbamoylaspartic acid
(D) is catalysed by orotate decarboxylase
49. Uric acid is NOT a breakdown product of :
(A) AMP (B) IMP
(C) GMP (D) CMP
50. During DNA replication, the sequence 5'-TpApGpAp-3' would produce which of the following complementary structures ?
(A) 5'-TpCpTpAp-3' (B) 5'-ApTpCpTp-3'
(C) 5'-UpCpUpAp-3' (D) 5'-GpCpUpAp-3'
51. One class of RNA characteristically contains methylated purines and pyrimidines. This RNA is :
(A) tRNA (B) mRNA
(C) rRNA (D) 16 S RNA
52. What is the maximum number of different amino acids in a polypeptide chain coded by the synthetic polyribonucleotide (UCAG) 5 ?
(A) One (B) Two
(C) Three (D) Four
53. The eukaryotic mRNA has a poly A tail comprising of :
(A) 50–250 (B) 200–250
(C) 50–500 (D) 250–380
54. Place the following in the chronological order of function : cDNA : gene : mRNA :
transcript :
(A) 2, 1, 3, 4 (B) 4, 1, 3, 2
(C) 4, 3, 2, 1 (D) 1, 2, 2, 3, 4
55. Which of the following could not be classified as a lipid ?
(A) steroids (B) fats and oils
(C) waxes (D) photosynthetic pigments
56. The role played by ATP in biochemical reactions is that of :
(A) a reducing agent (B) an energy-donor substance
(C) a coenzyme (D) an energy donor substance or a coenzyme
57. DNA, RNA and ATP are all composed of :
(A) nucleotides (B) purines
(C) nucleic acids (D) pentose acids
58. In which region of a mitochondria are enzymes of the citric acid cycle located ?
(A) outer membrane (B) inner membrane
(C) intermembrane space (D) matrix
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 10
59. Iron containing compounds that act as hydrogen acceptors in the respiratory chain are :
(A) flavoproteins (B) dehydrogenases
(C) cytochromes (D) oxidases
60. Which of these hormones inhibits FSH production in a female mammal ?
(A) estrogen (B) adrenalin
(C) thyroxine (D) testosterone
61. Acetylcholine is a :
(A) Neurotransmitter (B) B-vitamin
(C) Enzyme (D) Protein
62. Which of the following contains iodine ?
(A) Insulin (B) Thyroxine
(C) Oxytocin (D) Adrenalin
63. Intact duplex DNA is a substrate for :
(A) DNA pol I (B) DNA pol III
(C) RNA polymerase (D) DNA pol IV
64. Retinoic acid is a derivative of which Vitamin ?
(A) Vitamin A (B) Vitamin D
(C) Vitamin E (D) Vitamin K
65. Which of the following reactions uses all the phosphate of ATP ?
(A) formation of S-Adenosyl methionine (B) formation of TPP
(C) formation of PEP from pyruvate (D) none of these
66. The pH of stacking and running gel in SDS-PAGE respectively, are :
(A) 6.8 and 6.8 (B) 8.8 and 6.8
(C) 6.8 and 8.8 (D) 8.8 and 8.8
67. Macrocystic anemia can result from the deficiency of :
(A) folic acid (B) vitamin B2
(C) inositol (D) vitamin B12
68. Details of the citric acid cycle were worked out by the use of :
(A) X-ray crystallography (B) radioactive carbon compounds
(C) ultracentrifugation (D) electron microscopy
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 11 [Turn over
69. Which one of the following types of bonds or interactions is least important in determining the three-dimensional folding of most proteins ?
(A) Hydrogen bonds (B) Electrostatic bonds
(C) Hydrophobic interactions (D) Ester bonds
70. The Michaelis constant, Km is :
(A) numerically equal to ½ Vm
(B) dependent on the enzyme concentration
(C) independent of pH
(D) numerically equal to the substrate concentration that gives half-maximal velocity
71. Which one of the following statements is correct about trehalose ?
(A) It has glucose and fructose
(B) It is a reducing sugar
(C) It is hydrolyzed by -galactosidase to glucose
(D) It is a nonreducing sugar
72. The pka value of acetic acid is :
(A) 3.7 (B) 5.6
(C) 7.5 (D) 4.7
73. The pH of blood is :
(A) 7.0 (B) 6.8
(C) 7.4 (D) 7.6
74. Under physiological conditions, each of the following contains a high energy phosphate group EXCEPT :
(A) ATP (B) ADP
(C) AMP (D) Phosphoenolpyruvate
75. DNA fragments from 0.5-20 Kb can be resolved on agarose gel :
(A) 0.2% (B) 1.5%
(C) 0.7% (D) 2.0%
Question Booklet Series : A Sr. No. :
Important : Please consult your Admit Card / Roll No. Slip before filling your Roll Number on the Test Booklet and Answer Sheet.
Roll No.
O.M.R. Answer Sheet Serial No.
Signature of the Candidate :
Subject : M.Sc. (Hons. School)-Biochemistry
Time : 90 minutes Number of Questions : 75 Maximum Marks : 75
DO NOT OPEN THE SEAL ON THE BOOKLET UNTIL ASKED TO DO SO
INSTRUCTIONS
1. Write your Roll No. on the Question Booklet and also on the OMR Answer Sheet in the space provided and nowhere else.
2. Enter the Subject and Series Code of Question Booklet on the OMR Answer Sheet. Darken the corresponding bubble with Black Ball Point /Black Gel pen.
3. Do not make any identification mark on the Answer Sheet or Question Booklet.
4. To open the Question Booklet remove the paper seal (s) gently when asked to do so.
5. Please check that this Question Booklet contains 75 questions. In case of any discrepancy, inform the Assistant Superintendent within 10 minutes of the start of test.
6. Each question has four alternative answers (A, B, C, D) of which only one is correct. For each question, darken only one bubble (A or B or C or D), whichever you think is the correct answer, on the Answer Sheet with Black Ball Point / Black Gel pen.
7. If you do not want to answer a question, leave all the bubbles corresponding to that question blank in the Answer Sheet. No marks will be deducted in such cases.
8. Darken the bubbles in the OMR Answer Sheet according to the Serial No. of the questions given in the Question Booklet.
9. Negative marking will be adopted for evaluation i.e., 1/4th of the marks of the question will be deducted for each wrong answer. A wrong answer means incorrect answer or wrong filling of bubble.
10. For calculations, use of simple log tables is permitted. Borrowing of log tables and any other material is not allowed.
11. For rough work only the sheets marked “Rough Work” at the end of the Question Booklet be used.
12. The Answer Sheet is designed for computer evaluation. Therefore, if you do not follow the instructions given on the Answer Sheet, it may make evaluation by the computer difficult. Any esultant loss to the candidate on the above account, i.e., not following the instructions completely, shall be of the candidate only.
13. After the test, hand over the Question Booklet and the Answer Sheet to the Assistant Superintendent on duty.
14. In no case the Answer Sheet, the Question Booklet, or its part or any material copied/noted from this Booklet is to be taken out of the examination hall. Any candidate found doing so, would be expelled from the examination.
15. A candidate who creates disturbance of any kind or changes his/her seat or is found in possession of any paper possibly of any assistance or found giving or receiving assistance or found using any other unfair means during the examination will be expelled from the examination by the Centre Superintendent / Observer whose decision shall be final.
16. Telecommunication equipment such as pager, cellular phone, wireless, scanner, etc., is not
permitted inside the examination hall. Use of calculators is not allowed.
M.Sc.(Hons.School)-Biochemistry/A
1. Which of the following amino acids has not a charged side chain at physiologic pH ?
(A) Aspartic acid (B) Lysine
(C) Glutamic acid (D) Asparagine
2. Glutamine has :
(A) three titratable groups
(B) an amide group
(C) an acidic amino acid
(D) a side chain that cannot form hydrogen bonds in proteins
3. The GSH has following amino acids :
(A) Gln-Cys-Leu (B) Glu-Cys-Gly
(C) Asp-Ala-Gly (D) Glu-Asp-Gly
4. Edman degradation uses which reagent for sequencing a polypeptide ?
(A) Fluorotrinitrobenzene (B) Sanger's reagent
(C) Phenylisothiocyanate (D) Dansyl chloride
5. Which one is odd one out ?
(A) Eadie-Hofstee (B) Shine-Dalgarno
(C) Lineweaver-Burk (D) Michaelis-Menten
6. Which of the following is not part of protein sequencing ?
(A) Edman degradation (B) Amadori rearrangements
(C) HPLC (D) FAB-MS
7. A competitive inhibitor of an enzyme :
(A) increases Km without affecting Vm (B) decreases Km without affecting Vm
(C) increases Vm without affecting Km (D) decreases Vm without affecting Km
8. Restriction endonucleases as per EC numbering belong to class :
(A) 1 (B) 2
(C) 3 (D) 6
9. Large soluble proteins with many disulfide linked chains released into serum are :
(A) Albumins (B) Haemoglobin
(C) Collagen (D) IgG
10. Which of the following is most abundant protein secreted by fibroblasts ?
(A) Keratin (B) Collagen
(C) IgG (D) Alumin
11. What is the maximum insert size (Kb) of bacterial Plasmid ?
(A) 6–12 (B) 25–40
(C) 45–100 (D) 15–50
12. Fructosuria is the result of :
(A) a deficiency of phosphofructokinase (B) a deficiency of liver fructokinase
(C) elevated levels of liver aldolase B (D) a deficiency of liver hexokinase
13. Which one of the following is the major end product of protein-Nitrogen metabolism ?
(A) Glycine (B) Uric acid
(C) Urea (D) Arginine
14. A hereditary childhood disease, galactosemia, is characterized by a :
(A) high level of liver UDP-galactose
(B) lack of glucose 1-phosphate
(C) very low galactose 1-phosphate uridyltransferase activity in liver
(D) lack of galactokinase
15. Biosynthesis of glucuronic acid requires the :
(A) oxidation of UDP-glucose (B) oxidation of glucose 6-phosphate
(C) oxidation of 6-phosphogluconate (D) reduction of sorbitol
16. In Tay-Sachs disease lead to accumulation of GM2 due to :
(A) Hexosaminidase (B) Galactosidase
(C) Sulfatase (D) Neuranindase
17. Muscle glycogen cannot contribute directly to blood glucose levels because :
(A) muscle glycogen cannot be converted to glucose 6-phosphate
(B) muscle lacks glucose 6-phosphate phosphatase
(C) muscle contains no glucokinase
(D) muscle contains no glycogen phosphorylase
18. In the muscle, a sudden elevation of the Ca++ concentration will cause :
(A) activation of cyclic AMP-dependent protein kinase
(B) dissociation of cyclic AMP-dependent protein kinase into catalytic and regulatory subunits
(C) conversion of glycogen phosphorylase b to phosphorylase a
(D) conversion of cyclic AMP to AMP by phosphodiesterase
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 5 [Turn over
19. Mucopolysaccharidoses are inherited storage diseases. They are caused by :
(A) an increased rate of synthesis of proteoglycans
(B) the synthesis of polysaccharides with an altered structure
(C) defects in the degradation of proteoglycans
(D) the synthesis of abnormally small amounts of protein cores
20. Which one of the following is NOT a common feature of the carbohydrate structure in Nlinked and O-linked glycoproteins ?
(A) They may contain N-acetylneuraminic acid
(B) They may contain glucose
(C) Their degradation in vivo involves action of lysosomal enzymes
(D) Their synthesis involves participation of a lipid carrier
21. An uncoupler of oxidative phosphorylation such as dinitrophenol :
(A) inhibits respiration and ATP synthesis
(B) allows electron transport to proceed without ATP synthesis
(C) inhibits respiration without impairment of ATP synthesis
(D) specifically inhibits cytochrome b
22. The rate of glycolysis is controlled in part by inhibition of :
(A) NADH reductase (B) phosphofructokinase by citrate
(C) phosphofructokinase II (D) glucokinase by ATP
23. In pyruvate kinase deficiency, hemolysis of red cells occurs primarily because of increased intracellular levels of :
(A) lactate (B) pyruvate
(C) the ratio of ADP to ATP (D) 2,3-diphosphoglycerate
24. Which one of the following reactions is unique to gluconeogenesis ?
(A) Lactate →pyruvate
(B) Phosphoenolpyruvate (PEP)→pyruvate
(C) Oxaloacetate→phosphoenolypyruvate
(D) Glucose 6-phosphate→fructose 6-phosphate
25. Which of the following enzymic activities would you expect to be decreased in thiamine deficiency ?
(A) Pyruvate carboxylase (B) Isocitrate dehydrogenase
(C) Fumarase (D) -Ketoglutarate dehydrogenase
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 6
26. Which is the major phospholipid of eukaryotic cell membranes ?
(A) Cardiolipin (B) Phosphatidylcholine
(C) Cholesterol (D) Shingolipids
27. Substances that play a direct role in the synthesis of palmitate by the fatty acid synthetase complex include :
(A) covalently bound phosphopantetheine (B) covalently bound lipoic acid
(C) malonyl CoA (D) both (A) and (C)
28. In humans, carnitine :
(A) stimulates the activity of acetyl CoA carboxylase
(B) is important for fatty acid oxidation
(C) inhibits the formation of triacylglycerol
(D) none of these
29. In the major pathway by which liver produces ketone bodies, the immediate precursor of acetoacetate is :
(A) acetoacetyl CoA (B) -hydroxybutyrate
(C) 3-hydroxy-3-methylglutaryl CoA (D) two molecules of acetyl CoA
30. Hydrolysis of a mixture of phosphoglycerides will not yield which of the following compounds ?
(A) Choline (B) Glycerol
(C) Phosphate (D) Tryptophan
31. To be defined as a ganglioside, a lipid substance isolated from nerve tissue must contain in its structure :
(A) N-acetylneuraminic acid (NANA) hexoses, sphingosine, long chain fatty acids
(B) NANA, a hexose, a fatty acid, sphingosine, phosphorylcholine
(C) NANA, sphingosine, ethanolamine
(D) All of the above
32. Animals fed a high cholesterol diet exhibit decreased cholesterol synthesis by liver because of the inhibition of which one of the following enzymes ?
(A) 3-Hydroxy-3-methyl glutaryl CoA (HMG CoA) synthetase
(B) HMG CoA reductase
(C) Mevalonate kinase
(D) HMG CoA lyase
33. The lipoprotein particles that have the highest percent concentration of triacylglycerol are :
(A) the chylomicrons (B) the VLDL
(C) the LDL (D) the HDL
34. Chymotrypsin acts :
(A) in the stomach on peptide bonds formed by the amino acid glycine
(B) in the intestinal mucosa on carboxy-terminal amino acids in proteins and peptides
(C) in the intestine on peptide bonds formed by the amino acids arginine or aspartate
(D) in the intestine on peptide bonds formed by amino acids with aromatic side-chains
35. -Aminolevulinic acid synthase activity :
(A) is frequently increased in individuals treated with drugs, such as the barbiturate phenobarbital
(B) catalyses a rate-limiting reaction in porphyrin biosynthesis
(C) requires the cofactor pyridoxal phosphate
(D) all of the above
36. The catabolism of heme :
(A) occurs in the cells of the reticuloendothelial system
(B) involves the oxidative cleavage of the porphyrin ring
(C) results in the liberation of carbon monoxide
(D) all of the above
37. Insulin does all of the following EXCEPT :
(A) enhance glucose transport into muscles
(B) enhance glycogen formation of liver
(C) decrease lipolysis in adipose tissue
(D) enhance gluconeogenesis in liver
38. Ingestion of a metal consisting exclusively of protein would result in which of the following ?
(A) An increased release of insulin
(B) Hypoglycemia
(C) A decreased release of glucagon
(D) Ketoacidosis caused by the metabolism of ketogenic amino acids
39. Increased formation of ketone bodies during starvation is due to :
(A) mobilization of high-density lipoproteins
(B) formation of acetyl CoA in amounts that exceed the oxidative capacity of the liver
(C) decreased levels of free fatty acids in the liver
(D) a decreased mobilization of triacylglycerols from adipose tissue
40. The abbreviation "W" stands for which of the following amino acids ?
(A) Proline (B) Phenylalanine
(C) Tyrosine (D) Tryptophan
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 8
41. The coenzyme required in oxidative decarboxylation is :
(A) biotin (B) vitamin B12
(C) ascorbic acid (D) thiamine pyrophosphate
42. Which of the following reactions involves the participation of thiamine ?
(A) Lactate→pyruvate
(B) -ketoglutarate→succinyl CoA
(C) Acetyl CoA→malonyl CoA
(D) none of the above
43. Vitamin D :
(A) increases absorption of calcium from the intestine
(B) is not required in the diet of individuals exposed to sunlight
(C) is not really a vitamin because the active form, 1,25-dihydroxycholecalciferol can be synthesized in humans
(D) all of the above
44. -Tocopherol :
(A) functions primarily as an antioxidant
(B) deficiency is commonly found in adults
(C) requirements increase with the amount of polyunsaturated fatty acids in the diet
(D) both (A) and (C)
45. Complete acid hydrolysis of nucleic acids yields all of the following EXCEPT :
(A) phosphoric acid (B) purines
(C) pentoses (D) adenosine
46. Histones :
(A) are basic protein rich in lysine or arginine, or both
(B) are bound covalently to DNA
(C) have relatively high molecular weights (2,00,000 daltons or higher)
(D) are identical to protamines
47. The formation of uric acid from purines is catalysed by :
(A) adenylate deaminase (B) uricase
(C) urease (D) xanthine oxidase
48. The committed step in pyrimidine biosynthesis :
(A) provides a classic example of positive feedback control
(B) results in the formation of dihydroorotic acid
(C) is the formation of N-carbamoylaspartic acid
(D) is catalysed by orotate decarboxylase
49. Uric acid is NOT a breakdown product of :
(A) AMP (B) IMP
(C) GMP (D) CMP
50. During DNA replication, the sequence 5'-TpApGpAp-3' would produce which of the following complementary structures ?
(A) 5'-TpCpTpAp-3' (B) 5'-ApTpCpTp-3'
(C) 5'-UpCpUpAp-3' (D) 5'-GpCpUpAp-3'
51. One class of RNA characteristically contains methylated purines and pyrimidines. This RNA is :
(A) tRNA (B) mRNA
(C) rRNA (D) 16 S RNA
52. What is the maximum number of different amino acids in a polypeptide chain coded by the synthetic polyribonucleotide (UCAG) 5 ?
(A) One (B) Two
(C) Three (D) Four
53. The eukaryotic mRNA has a poly A tail comprising of :
(A) 50–250 (B) 200–250
(C) 50–500 (D) 250–380
54. Place the following in the chronological order of function : cDNA : gene : mRNA :
transcript :
(A) 2, 1, 3, 4 (B) 4, 1, 3, 2
(C) 4, 3, 2, 1 (D) 1, 2, 2, 3, 4
55. Which of the following could not be classified as a lipid ?
(A) steroids (B) fats and oils
(C) waxes (D) photosynthetic pigments
56. The role played by ATP in biochemical reactions is that of :
(A) a reducing agent (B) an energy-donor substance
(C) a coenzyme (D) an energy donor substance or a coenzyme
57. DNA, RNA and ATP are all composed of :
(A) nucleotides (B) purines
(C) nucleic acids (D) pentose acids
58. In which region of a mitochondria are enzymes of the citric acid cycle located ?
(A) outer membrane (B) inner membrane
(C) intermembrane space (D) matrix
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 10
59. Iron containing compounds that act as hydrogen acceptors in the respiratory chain are :
(A) flavoproteins (B) dehydrogenases
(C) cytochromes (D) oxidases
60. Which of these hormones inhibits FSH production in a female mammal ?
(A) estrogen (B) adrenalin
(C) thyroxine (D) testosterone
61. Acetylcholine is a :
(A) Neurotransmitter (B) B-vitamin
(C) Enzyme (D) Protein
62. Which of the following contains iodine ?
(A) Insulin (B) Thyroxine
(C) Oxytocin (D) Adrenalin
63. Intact duplex DNA is a substrate for :
(A) DNA pol I (B) DNA pol III
(C) RNA polymerase (D) DNA pol IV
64. Retinoic acid is a derivative of which Vitamin ?
(A) Vitamin A (B) Vitamin D
(C) Vitamin E (D) Vitamin K
65. Which of the following reactions uses all the phosphate of ATP ?
(A) formation of S-Adenosyl methionine (B) formation of TPP
(C) formation of PEP from pyruvate (D) none of these
66. The pH of stacking and running gel in SDS-PAGE respectively, are :
(A) 6.8 and 6.8 (B) 8.8 and 6.8
(C) 6.8 and 8.8 (D) 8.8 and 8.8
67. Macrocystic anemia can result from the deficiency of :
(A) folic acid (B) vitamin B2
(C) inositol (D) vitamin B12
68. Details of the citric acid cycle were worked out by the use of :
(A) X-ray crystallography (B) radioactive carbon compounds
(C) ultracentrifugation (D) electron microscopy
M.Sc.(Hons.School)-Biochemistry-A/FRH-41377 11 [Turn over
69. Which one of the following types of bonds or interactions is least important in determining the three-dimensional folding of most proteins ?
(A) Hydrogen bonds (B) Electrostatic bonds
(C) Hydrophobic interactions (D) Ester bonds
70. The Michaelis constant, Km is :
(A) numerically equal to ½ Vm
(B) dependent on the enzyme concentration
(C) independent of pH
(D) numerically equal to the substrate concentration that gives half-maximal velocity
71. Which one of the following statements is correct about trehalose ?
(A) It has glucose and fructose
(B) It is a reducing sugar
(C) It is hydrolyzed by -galactosidase to glucose
(D) It is a nonreducing sugar
72. The pka value of acetic acid is :
(A) 3.7 (B) 5.6
(C) 7.5 (D) 4.7
73. The pH of blood is :
(A) 7.0 (B) 6.8
(C) 7.4 (D) 7.6
74. Under physiological conditions, each of the following contains a high energy phosphate group EXCEPT :
(A) ATP (B) ADP
(C) AMP (D) Phosphoenolpyruvate
75. DNA fragments from 0.5-20 Kb can be resolved on agarose gel :
(A) 0.2% (B) 1.5%
(C) 0.7% (D) 2.0%
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