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ENZYMES- Part 9
See all quizzes of ENZYMES- Part 9 here:
1. An important finding in Hyperammonemia
type II is
(A) Increased serum gluatmine level
(B) Enlarged liver
(C) Mental retardation
(D) Increased carbamoyl phosphate synthetase
level
2. Absence of the enzyme argininosuccinate
synthetase causes
(A) Argininosuccinic aciduria
(B) Hyperargininemia
(C) Tricorrhexis nodosa
(D) Citrullinemia
3. Tricorrhexis nodosa is a characteristic finding
of
(A) Argininosuccinic aciduria
(B) Citrullinemia
(C) Phenylketonuria
(D) Hyperargininemia
4. Elevated blood argininosuccinate level is
found in
(A) Hyperargininemia
(B) Argininosuccinic aciduria
(C) Citrullinemia
(D) Tyrosinosis
5. Hyperargininemia, a defect in urea synthesis
develops due to deficiency of the
enzyme:
(A) Ornithine transcarbamoylase
(B) Argininosuccinase
(C) Arginase
(D) Argininosuccinate synthetase
6. Albinism is due to deficiency of the enzyme:
(A) Phenylalanine hydroxylase
(B) Tyrosinase
(C) p-Hydroxyphenylpyruvic acid oxidase
(D) Tyrosine dehydrogenase
7. Neonatal tyrosinemia is due to deficiency
of the enzyme:
(A) p-Hydroxyphenylpyruvate hydroxylase
(B) Fumarylacetoacetate hydrolase
(C) Phenylalanine hydroxylase
(D) Tyrosine dehydrogenase
8. Which of the following is a substratespecific
enzyme?
(A) Hexokinase (B) Thiokinase
(C) Lactase (D) Aminopeptidase
9. Coenzymes combine with
(A) Proenzymes (B) Apoenzymes
(C) Holoenzymes (D) Antienzymes
10. Coenzymes are required in which of the
following reactions?
(A) Oxidation-reduction
(B) Transamination
(C) Phosphorylation
(D) All of these
11. Which of the following coenzyme takes
part in hydrogen transfer reactions?
(A) Tetrahydrofolate (B) Coenzyme A
(C) Coenzyme Q (D) Biotin
12. Which of the following coenzyme takes
part in oxidation-reduction reactions?
(A) Pyridoxal phosphate
(B) Lipoic acid
(C) Thiamin diphosphate
(D) None of these
13. In conversion of glucose to glucose-6-
phsophate, the coenzyme is
(A) Mg++
(B) ATP
(C) Both (A) and (B)
(D) None of these
14. A coenzyme required in transamination
reactions is
(A) Coenzyme A (B) Coenzyme Q
(C) Biotin (D) Pyridoxal phosphate
15. Coenzyme A contains a vitamin which is
(A) Thiamin (B) Ascorbic acid
(C) Pantothenic acid (D) Niacinamide
16. Cobamides contain a vitamin which is
(A) Folic acid (B) Ascorbic acid
(C) Pantothenic acid (D) Vitamin B12
17. A coenzyme required in carboxylation
reactions is
(A) Lipoic acid (B) Coenzyme A
(C) Biotin (D) All of these
18. Which of the following coenzyme takes
part in tissue respiration?
(A) Coenzyme Q (B) Coenzyme A
(C) NADP (D) Cobamide
19. The enzyme hexokinase is a
(A) Hydrolase (B) Oxidoreductase
(C) Transferase (D) Ligase
20. Which of the following is a proteolytic
enzyme?
(A) Pepsin (B) Trypsin
(C) Chymotrypsin (D) All of these
21. Enzymes which catalyse binding of two
substrates by covalent bonds are known as
(A) Lyases (B) Hydrolases
(C) Ligases (D) Oxidoreductases
22. The induced fit model of enzyme action
was proposed by
(A) Fischer (B) Koshland
(C) Mitchell (D) Markert
23. Allosteric inhibition is also known as
(A) Competitive inhibition
(B) Non-competitive inhibition
(C) Feedback inhibition
(D) None of these
24. An allosteric enzyme is generally inhibited
by
(A) Initial substrate of the pathway
(B) Substrate analogues
(C) Product of the reaction catalysed by allosteric
enzyme
(D) Product of the pathway
25. 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
26. In Lineweaver-Burk plot, the y-intercept
represents
(A) Vmax (B) Km
(C) Km (D) 1/Km
27. 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
28 Competitive inhibitors
(A) Decrease the Km (B) Decrease the Vmax
(C) Increase the Km (D) Increase the Vmax
29. Competitive inhibition can be relieved by
raising the
(A) Enzyme concentration
(B) Substrate concentration
(C) Inhibitor concentration
(D) None of these
30. Physostigmine is a competitive inhibitor
of
(A) Xanthine oxidase
(B) Cholinesterase
(C) Carbonic anhydrase
(D) Monoamine oxidase
