I. Start the exam by click the “Start” button
ENZYMES- Part 10
See all quizzes of ENZYMES- Part 10 here:
1 Carbonic anhydrase is competitively
inhibited by
(A) Allopurinol (B) Acetazolamide
(C) Aminopterin (D) Neostigmine
2. Serum lactate dehydrogenase rises in
(A) Viral hepatitis
(B) Myocardial infarction
(C) Carcinomatosis
(D) All of these
3. Which of the following serum enzyme
rises in myocardial infarction:
(A) Creatine kinase (B) GOT
(C) LDH (D) All of these
4. From the following myocardial infarction,
the earliest serum enzyme to rise is
(A) Creatine Kinase (B) GOT
(C) GPT (D) LDH
5. Proenzymes:
(A) Chymotrysinogen (B) Pepsinogen
(C) Both (A) and (B) (D) None of these
6. Alkaline phosphatase is present in
(A) Liver (B) Bones
(C) Placenta (D) All of these
7. Which of the following isoenzyme of
lactate dehydrogenase is raised in serum
in myocardial infarction:
(A) LD1 (B) LD2
(C) LD1 and LD2 (D) LD5
8. Enzymes which are always present in an
organism are known as
(A) Inducible enzymes
(B) Constitutive enzymes
(C) Functional enzymes
(D) Apoenzymes
9. Inactive precursors of enzymes are known
as
(A) Apoenzymes (B) Coenzymes
(C) Proenzymes (D) Holoenzymes
10. Whcih of the following is a proenzyme?
(A) Carboxypeptidase
(B) Aminopeptidase
(C) Chymotrypsin
(D) Pepsinogen
11. Allosteric enzymes regulate the formation
of products by
(A) Feedback inhibition
(B) Non-competitive inhibition
(C) Competitive inhibition
(D) Repression-derepression
12 Regulation of some enzymes by covalent
modification involves addition or removal
of
(A) Acetate (B) Sulphate
(C) Phosphate (D) Coenzyme
13. Covalent modification of an enzyme
generally requires a
(A) Hormone (B) cAMP
(C) Protein kinase (D) All of these
14. An inorganic ion required for the activity
of an enzyme is known as
(A) Activator (B) Cofactor
(C) Coenzyme (D) None of these
15. The first enzyme found to have isoenzymes
was
(A) Alkaline Phosphatase
(B) Lactate dehydrogenase
(C) Acid Phosphatase
(D) Creatine kinase
16. Lactate dehydrogenase is located in
(A) Lysosomes (B) Mitochondria
(C) Cytosol (D) Microsomes
17. Lactate dehydrogenase is a
(A) Monomer (B) Dimer
(C) Tetramer (D) Hexamer
18. Ceruloplasmin is absent in
(A) Cirrhosis of liver (B) Wilson’s disease
(C) Menke’s disease (D) Copper deficiency
19. Ceruloplasmin oxidizes
(A) Copper (B) Iron
(C) Both (A) and (B) (D) None of these
20. Creatine kinase is present in all of the
following except
(A) Liver (B) Myocardium
(C) Muscles (D) Brain
21. Alkaline phosphatase is present in
(A) Liver (B) Bones
(C) Intestinal mucosa (D) All of these
22. All of the following are zinc-containing
enzymes except
(A) Acid Phosphatase
(B) Alkaline Phosphatase
(C) Carbonic anhydrase
(D) RNA polymerase
23. All of the following are iron-containing
enzymes except
(A) Carbonic anhydrase
(B) Catalase
(C) Peroxidase
(D) Cytochrome oxidase
24. Biotin is a coenzyme for
(A) Pyruvate dehydrogenase
(B) Pyruvate carboxylase
(C) PEP carboxykinase
(D) Glutamate pyruvate transminase
25. 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
26. Kinetics of an allosteric enzyme are
explained by
(A) Michaelis-Menten equation
(B) Lineweaver-Burk plot
(C) Hill plot
(D) All of these
27. Covalent modification of an enzyme
usually involves phosphorylation /
dephosphorylation of
(A) Serine residue
(B) Proline residue
(C) Hydroxylysine residue
(D) Hydroxyproline residue
28. Vmax of an enzyme may be affected by
(A) pH
(B) Temperature
(C) Non-competitive inhibitors
(D) All of these
29. In enzyme assays, all the following are
kept constant except
(A) Substrate concentration
(B) Enzyme concentration
(C) pH
(D) Temperature
30. 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
