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ENZYMES- Part 12
See all quizzes of ENZYMES- Part 12 here:
1 Phosphofructokinase is allosterically
inhibited by
(A) Fructose-1, 6-biphosphate
(B) Lactate
(C) Pyruvate
(D) Citrate
2. Glucose-6-phosphate is an allosteric
inhibitor of
(A) Glucokinase
(B) Hexokinase
(C) Phosphohexose isomerase
(D) None of these
3. ATP is a co-substrate as well as an allosteric
inhibitor of
(A) Phosphofructokinase
(B) Hexokinase
(C) Glucokinase
(D) None of these
4. Complete oxidation of one molecule of
glucose into CO2 and H2O yields
(A) 8 ATP equivalents
(B) 15 ATP equivalents
(C) 30 ATP equivalents
(D) 38 ATP equivalents
5. A unique by-product of glycolysis in
erythrocytes is
(A) Lactate
(B) 1, 3-Biphosphoglycerate
(C) 2, 3-Biphosphoglycerate
(D) All of these
6. Which of the following enzymes incorporates
inorganic phosphate into the substrate?
(A) Phosphoglycerate kinase
(B) Glyceraldehyde-3-phosphate dehydrogenase
(C) Pyruvate kinase
(D) Enolase
7. Rapoport-Luebering cycle is located in
(A) Liver (B) Muscles
(C) Brain (D) Erythrocytes
8. Glycerol can enter glycolytic pathway via
(A) Dihydroxyacetone phosphate
(B) 1, 3-Biphospoglycerate
(C) 3-Phosphoglycerate
(D) 2-Phosphoglycerate
9. HMP shunt is present in
(A) Erythrocytes (B) Liver
(C) Testes (D) All of these
10. Glucose-6-phosphate dehydrogenase is
induced by
(A) 6-Phosphogluconolactone
(B) Glucose-6-phosphate
(C) Ribose-5-phosphate
(D) Insulin
11. The decarboxylation reaction in HMP
shunt is catalysed by
(A) Gluconolactone hydrolase
(B) 6-Phosphogluconate dehydrogenase
(C) 6-Phosphogluconate decarboxylase
(D) Transaldolase
12. The first pentose formed in HMP shunt is
(A) Ribose-5-phosphate (B) Ribulose-5-phosphate
(C) Xylose-5-phosphate (D) Xylulose-5-phosphate
13. The regulatory enzyme in HMP shunt is
(A) Glucose-6-phosphate dehydrogenase
(B) 6-Phosphogluconate dehydrogenase
(C) Both (A) and (B)
(D) None of these
14. The rate of HMP shunt reactions is
(A) Increased by Insulin
(B) Increased in diabetes mellitus
(C) Increased by glucagons
(D) Increased in starvation
15. Glycogenesis requires
(A) GTP (B) CTP
(C) UTP (D) None of these
16. Glycogen synthetase catalyses the
formation of
(A) α−1, 4-Glycosidic bonds
(B) α−1, 6-Glycosidic bonds
(C) Both (A) and (B)
(D) None of these
17. Glycogenoloysis is increased by
(A) Glucagon (B) Insulin
(C) Epinephrine (D) cAMP
18. Hepatic glycogenoloysis is increased by
(A) Insulin (B) Glucagon
(C) Epinephrine (D) Glucocorticoids
ENZYMES 163
19. Glycogen phosphorylase liberates the
following from glycogen
(A) Glucose
(B) Glucose-6-phosphate
(C) Glucose-1-phosphate
(D) Maltose
20. After the action of phosphorylase, glycogen
is converted into
(A) Amylopectin (B) dextrin
(C) Amylose (D) Maltose
21. Glucose-1-phosphate liberated from
glycogen cannot be converted into free
glucose in
(A) Liver (B) Kidneys
(C) Muscles (D) Brain
22. A coenzyme present in phosphorylase is
(A) NAD
(B) Pyridoxal phosphate
(C) Thiamin pyrophosphate
(D) Coenzyme A
23. If glucose-1-phosphate formed by
glycogenoloysis in muscles is oxidized to
CO2 and H2O, the energy yield will be
(A) 2 ATP equivalents (B) 3 ATP equivalents
(C) 4 ATP equivalents (D) 8 ATP equivalents
24. A molecule of phosphorylase kinase is
made up of
(A) 4 subunits (B) 8 subunits
(C) 12 subunits (D) 16 subunits
25. Cyclic AMP binds to
(A) Catalytic subunits of protein kinase
(B) Regulatory subunits of protein kinase
(C) Catalytic subunits of phosphorylase kinase
(D) Regulatory subunits of phosphorylase kinase
26. Glucose is the only source of energy for
(A) Myocardium (B) Kidneys
(C) Erythrocytes (D) Thrombocytes
27. Glycerol-3-phosphate for the synthesis of
triglycerides in adipose tissue is derived
from
(A) Phosphatidic acid (B) Diacylglycerol
(C) Glycerol (D) Glucose
28. Gluconeogenesis does not occur in
(A) Brain (B) Kidneys
(C) Muscles (D) Liver
29. Glucose cannot be synthesized from
(A) Glycerol (B) Lactate
(C) Alanine (D) Leucine
30. Coenzyme for phosphoenolpyruvate
carboxykinase is
(A) ATP (B) ADP
(C) GTP (D) GDP
