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ENZYMES- Part 4
See all quizzes of ENZYMES- Part 4 here:
1 One of the enzymes regulating glycolysis
is
(A) Phosphofructokinase
(B) Glyceraldehyde-3-phosphate dehydrogenase
(C) Phosphotriose isomerase
(D) Phosphohexose isomerase
2. 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
3. A reaction which may be considered an
isomerisation is
(A) Glucose 6-Phosphate fructose 6 phosphate
(B) 3-Phosphoglycerate 2-phosphoglycerate
(C) 2-phosphoglycerate phosphoenolpyruvate
(D) Pyruvate Lactate
4. The net number of ATP formed per mole
of glucose in anaerobic glycolysis is
(A) 1 (B) 2
(C) 6 (D) 8
5. Pyruvate dehydrogenase a multienzyme
complex is required for the production of
(A) Acetyl-CoA
(B) Lactate
(C) Phosphoenolpyruvate
(D) Enolpyruvate
6. Dietary deficiency of thiamin inhibits the
activity of the enzyme:
(A) Pyruvate kinase
(B) Pyruvate dehydrogenase
(C) Phosphofructokinase
(D) Enolase
7. Pyruvate dehydrogenase activity is
inhibited by
(A) Mercury (B) Zinc
(C) Calcium (D) Sodium
8. 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
9. All the enzymes of glycolysis pathway are
found in
(A) Extramitochondrial soluble fraction of the cell
(B) Mitochondria
(C) Nucleus
(D) Endoplasmic reticulum
10. Most major metabolic pathways are considered
mainly either anabolic or catabolic.
Which of the following pathway
is most correctly considered to be amphibolic?
(A) Citric acid cycle (B) Gluconeogenesis
(C) Lipolysis (D) Glycolysis
11. 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
12. 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 α -ketoglutarate catalysed by
isocitrate dehydrogenase
13. The substance which may be considered
to play a catalytic role in citric acid cycle is
(A) Oxaloacetate (B) Isocitrate
(C) Malate (D) Fumarate
14. An enzyme of the citric acid cycle also
found outside the mitochondria is
(A) Isocitrate dehydrogenase
(B) Citrate synthetase
(C) α-Ketoglutarate dehydrogenase
(D) Malate dehydrogenase
15. The reaction catalysed by α-ketoglutarate
dehydrogenase in the citric acid cycle
requires
(A) NAD (B) NADP
(C) ADP (D) ATP
16. 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
17. In TCA cycle, oxalosuccinate is converted
to α-ketoglutarate by the enzyme:
(A) Fumarase
(B) Isocitrate dehydrogenase
(C) Aconitase
(D) Succinase
18. The enzyme -ketoglutarate dehydrogenase
in the citric acid cycle requires
(A) Lipoate (B) Folate
(C) Pyridoxine (D) Inositol
19. The example of generation of a high
energy phosphate at the substrate level
in the citric acid cycle is the reaction:
(A) Isocitrate α-Ketoglutarate
(B) Succinate α-fumarate
(C) Malate α-oxaloacetate
(D) Succinyl CoA α-Succinate
20. Fluoroacetate inhibits the reaction of citric
acid cycle:
(A) Isocitrate α-Ketoglutarate
(B) Fumarate α-Malate
(C) Citrate α-cis-aconitate
(D) Succinate α-fumarate
21. Formation of succinyl-CoA from α-Ketoglutarate
is inhibited by
(A) Fluoroacetate (B) Arsenite
(C) Fluoride (D) Iodoacetate
22. The number of ATP molecules generated
for each turn of the citric acid cycle is
(A) 8 (B) 12
(C) 24 (D) 38
23. Oxidation of one molecule of glucose
yields
(A) 12 ATP (B) 24 ATP
(C) 38 ATP (D) 38 ATP
24. 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
25. Mitochondrial membrane is freely
preamble to
(A) Pyruvate (B) Malate
(C) Oxaloacetate (D) Fumarate
26. The reaction of Kreb’s cycle which does
not require cofactor of vitamin B group is
(A) Citrate isocitrate
(B) α -Ketoglutarate succinate
(C) Malate oxaloacetate
(D) Succinate fumarate
27. The coenzyme not involved in the
formation of acetyl-CoA from pyruvate is
(A) TPP (B) Biotin
(C) NAD (D) FAD
28. A carrier molecule in the citric acid cycle is
(A) Acetyl-CoA (B) Citrate
(C) Oxaloacetate (D) Malate
29. A specific inhibitor for succinate dehydrogenase
is
(A) Arsenine (B) Arsenite
(C) Citrate (D) Fluoride
30. The rate of citric acid cycle is controlled
by the allosteric enzyme:
(A) Aconitase
(B) Fumarase
(C) Fumarase
(D) Malate dehydrogenase
