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ENZYMES- Part 6
See all quizzes of ENZYMES- Part 6 here:
1 An enzyme involved in gluconeogenesis is
(A) Pyruvate kinase
(B) Pyruvate carboxylase
(C) Hexokinase
(D) Phosphohexose isomerase
2. The enzyme pyruvate carboxylase is
present in
(A) Cytosol (B) Mitochondria
(C) Nucleus (D) Golgi bodies
3. The enzyme phosphoenolpyruvate
carboxykinase catalyses the conversion
of oxaloacetate to phosphoenolpyruvate
requires
(A) ATP (B) ADP
(C) AMP (D) GTP
4. The enzyme glucose 6-phosphatase is
present in
(A) Liver (B) Muscle
(C) Adipose tissue (D) Brain
5. In gluconeogensis, an allosteric activator
required in the synthesis of oxaloacetate
from bicarbonate and pyruvate, which is
catalysed by the enzyme pyruvate
carboxylase is
(A) Acetyl CoA (B) Succinate
(C) Isocitrate (D) Citrate
6. The number of ATP molecules required to
convert 2 molecules of lactate into glucose
in mammalian liver is
(A) 2 (B) 4
(C) 5 (D) 6
7. For conjugation with many enogenous
and exogenous substances before elimination
in urine, the uronic acid pathway
provides
(A) Active glucuronate (B) Gulonate
(C) Xylulose (D) Xylitol
8. UDP glucose is converted to UDP
glucurronate, a reaction catalysed by UDP
glucose dehydrogenase requires
(A) NAD+ (B) FAD
(C) NADP (D) FMN
9. Pentosuria is a rare hereditary disease is
characterized by increased urinary
excretion of
(A) L-xylulose
(B) Xylitol
(C) Xylulose 5-phosphate
(D) Ribose 5-phosphate
10. The enzyme involved in essential
pentosuria is
(A) Reductase (B) Hydroxylase
(C) Isomerase (D) Racemase
11. Galactose is synthesized from glucose in
(A) Mammary gland (B) Intestine
(C) Kidney (D) Adipose tissue
12. Galactose is readily converted to glucose in
(A) Liver (B) Intestine
(C) Kidney (D) Adipose tissue
13. Galactose 1-phosphate is converted to
uridine diphosphate galactose, the
reaction is catalysed by the enzyme:
(A) Glactokinase
(B) Galactose 1-phosphate uridyl transferase
(C) Uridine diphospho galactose 4-epimerase
(D) UDP glucose pyrophosphorylase
14. The best known cause of galactosemia is
the deficiency of
(A) Galactose 1-phosphate and uridyl transferase
(B) Phosphoglucomutase
(C) Galactokinase
(D) Lactose synthase
15 Conversion of fructose to sorbitol is
catalysed by the enzyme:
(A) Sorbitol dehydrogenase
(B) Aldose reductase
(C) Fructokinase
(D) Hexokinase
16. A specific fructokinase present in liver has
a very high affinity for its substrate
because
(A) Km for fructose is very high
(B) Km for fructose is very low
(C) Activity is affected by fasting
(D) Activity is affected by insulin
17. Insulin has no effect on the activity of the
enzyme:
(A) Glycogen synthetase
(B) Fructokinase
(C) Pyruvate kinase
(D) Pyruvate dehydrogenase
18. The pathogenesis of diabetic cataract
involves accumulation of
(A) Galactose (B) Mannitol
(C) Sorbitol (D) Pyruvate
19. Hereditary fructose intolerance involves
the absence of the enzyme:
(A) Aldalose B
(B) Fructokinase
(C) Triokinase
(D) Phosphotriose isomerase
20. Essential fructosuria is characterized by
the lack of the hepatic enzyme:
(A) Phosphohexose isomerase
(B) Aldalose A
(C) Aldolase B
(D) Fructokinase
21. In normal individuals glycosuria occurs
when the venous blood glucose concentration
exceeds
(A) 5–6 mmol/L
(B) 7–8 mmol/L
(C) 8.5–9 mmol/L
(D) 9.5–10 mmol/L
22. Phlorizin inhibits
(A) Renal tubular reabsorption of glucose
(B) Glycolysis
(C) Gluconeogenesis
(D) Glycogenolysis
23. Renal glycosuria is characterized by
(A) Hyperglycemia
(B) Hyperglycemia with glycosuria
(C) Normal blood glucose level with glycosuria
(D) Hyperglycemia with ketosis
24. Acute hemolytic anemia in person’s sensitive
to the Fava beans is due to the deficiency
of the enzyme:
(A) Pyruvate dehydrogenase
(B) G-6-PD
(C) Aconitase
(D) Transketolase
25 Acute hemolytic episode after administration
of antimalarial, primaquin, is due to
deficiency of the enzyme:
(A) 6-Phosphogluconate dehydrogenase
(B) Glucose-6-phosphate dehydrogenase
(C) Epimerase
(D) Transketolase
26. The pH optima of gastric lipase is
(A) 3.0–6.0 (B) 1.0–2.0
(C) 8.0 (D) 8.6
27. The optimum pH of pancreatic lipase is
(A) 2.0 (B) 4.0
(C) 6.0 (D) 8.0
28. Gastric lipae is activated in the presence
of
(A) Bile salts (B) Cu++
(C) K+ (D) Na+
29. An example of enzyme inhibition:
(A) Reversible inhibition
(B) Irreversible inhibition
(C) Allosteric inhibition
(D) All of these
30. The formation of Δ2-trans-enoyl-CoA from
acyl-CoA requires the enzyme:
(A) Acyl-CoA synthetase
(B) Acyl-CoA dehydrogenase
(C) 3-Hydroxy acyl-CoA dehydrogenase
(D) Thiolase
