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ENZYMES- Part 14
See all quizzes of ENZYMES- Part 14 here:
1 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
2. A substrate for the enzyme aldolase is
(A) galactose-6-phosphate
(B) isocitric acid
(C) Glucose-1-phosphate
(D) Fructose 1, 6 diphosphate
3. Decarboxylation of α-keto acids requires
(A) Thiamine pyrophosphate, FAD, NAD+
(B) Flavin mononucleotide
(C) NADP+
(D) NAD+ only
4. Coenzyme A contains the vitamin:
(A) Riboflavin (B) Pantothenic acid
(C) Pyridoxine (D) Thiamine
5. Which of the following is not a component
of coenzyme A?
(A) Adenylic acid
(B) Pantothenic acid
(C) β -mercaptoethylamine
(D) Deoxyadenylic acid
6. 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
7. The following reaction is characteristic of
what type of enzymes?
2H2O2 → 2H2O + O2
(A) Peroxides
(B) Catalase
(C) Dehydrogenase
(D) Copper containing oxidases
8. Of Which warburg’s yellow enzyme
contains as a prosthetic group?
(A) Thiamine pyrophosphate
(B) Biotin
(C) NAD+
(D) Riboflavin-5-phosphate
9. Dehydrogenases utilize, as coenzymes, all
of the following except
(A) NAD+ (B) NADP+
(C) FAD (D) FH4
10. Urea is produced physiologically by the
action of the enzyme:
(A) Urease (B) Glutaminase
(C) Arginase (D) None of these
11. Urease is a
(A) Lyase (B) Ligase
(C) Isomerase (D) Hydrolase
12. 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
13. 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
14. The inhibition of succinate dehydrogenase
by malonate by
(A) Competitive inhibition
(B) Non-competitive inhibition
(C) Uncompetitive inhibition
(D) Feedback inhibition
15. Cobamide coenzymes are
(A) Vitamin B1 (B) Riboflavin
(C) Pyridoxine (D) Vitamin B12
16. 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
17. FAD containing enzyme, catalyzing
formation of α, β unsaturated fatty acyl
CoA derivative.
(A) Acyl CoA dehydrogenase
(B) Enoyl hydrase
(C) β-OH acyl CoA dehydrogenase
(D) Thiolase
18. Immobilized enzymes:
(A) Potentiation of activity
(B) Presentation of activity
(C) Preparation of activity
(D) All of these
19. This catalyzes formation of CoA derivatives
from fatty acid, CoA and ATP:
(A) Acyl CoA dehydrogenase
(B) Enoyl hydrase
(C) β-OH acyl CoA dehydrogenase
(D) Thio kinase
20. Fructose 2, 3 bi phosphate is a powerful
allosteric activator of
(A) Fructose 1, 6 diphosphatase
(B) Phosphofructokinase
(C) Hexokinase
(D) Fructokinase
21. ‘Clearing factor’ is
(A) Lipoprotein lipase
(B) Crotonase
(C) 7-dehydro cholesterol
(D) β-sitosterol
22. Maltase attacks only
(A) α-glucosides (B) β-glucosides
(C) Starch (D) Dextrins
23. Pepsin is
(A) Exo-peptidase (B) Endo-peptidase
(C) Carboxy peptidase(D) Amino peptidase
24. An enzyme in saliva which hydrolyzes
starch is
(A) Pepsinogen (B) Chymotrysin
(C) α-Amylase (D) Malate
25. 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
26. 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
27. Schardinger’s enzyme is
(A) Lactate dehydrogenase
(B) Xanthine dehydrogenase
(C) Uric oxidase
(D) L amino acid dehydrogenase
28. Tryptophan pyrolase is currently known
as
(A) Tryptophan deaminase
(B) Tryptophan dioxygenase
(C) Tryptophan mono oxygenase
(D) Tryptophan decarboxylase
29. An enzyme which brings about lysis of
bacterial cell wall is
(A) Amylase (B) Lysozyme
(C) Trypsin (D) Lipase
30. Trypsin has no action on
(A) Hemoglobin (B) Albumin
(C) Histone (D) DNA
