BIOCHEMISTRY MCQs WITH ANSWER

BIOCHEMISTRY MCQs WITH ANSWER

01. One of the following statement is correct:
(A) Glycogen synthase ‘a’ is the phosphorylated
(B) cAMP converts glycogen synthase b to ‘a’
(C) Insulin converts glycogen synthase b to a
(D) UDP glucose molecules interact and grow into a Glycogen tree

02. Amylo 1, 6 glucosidase is called
(A) Branching enzyme
(B) debranching enzyme
(C) Glucantransferase
(D) Phosphorylase

03. Glucose enters the cells by
(A) insulin independent transport
(B) insulin dependent transport
(C) enzyme mediated transport
(D) Both (A) and (B)

04. Glycogen while being acted upon by active phosphorylase is converted first to
(A) Glucose
(B) Glucose 1-phosphate and Glycogen with 1 carbon less
(C) Glucose-6-phosphate and Glycogen with 1 carbon less
(D) 6-Phosphogluconic acid

05. When O2 supply is inadequate, pyruvate is converted to
(A) Phosphopyruvate
(B) Acetyl CoA
(C) Lactate
(D) Alanine

06. Reactivation of inactive liver phosphorylase is normally favoured by
(A) Insulin
(B) Epinephrine
(C) ACTH
(D) Glucagon

07. Before pyruvic acid enters the TCA cycle it must be converted to
(A) Acetyl CoA
(B) Lactate
(C) α-ketoglutarate
(D) Citrate

08. The hydrolysis of Glucose-6-phosphate is catalysed by a specific phosphatase which is found only in
(A) Liver, intestines and kidneys
(B) Brain, spleen and adrenals
(C) Striated muscle
(D) Plasma

09. The formation of citrate from oxalo acetate and acetyl CoA is
(A) Oxidation
(B) Reduction
(C) Condensation
(D) Hydrolysis

10. Which one of the following is a rate limiting enzyme of gluconeogenesis?
(A) Hexokinase
(B) Phsophofructokinase
(C) Pyruvate carboxylase
(D) Pyruvate kinase

11. The number of ATP produced in the succinate dehydrogenase step is
 (A) 1
 (B) 2
 (C) 3
 (D) 4

 12. Which of the following reaction gives lactose?
 (A) UDP galactose and glucose
 (B) UDP glucose and galactose
 (C) Glucose and Galactose
 (D) Glucose, Galactose and UTP

 13. UDP Glucuronic acid is required for the biosynthesis of
 (A) Chondroitin sulphates
 (B) Glycogen
 (C) Lactose
 (D) Starch

 14. Which one of the following can covert glucose to vitamin C?
(A) Albino rats
(B) Humans
 (C) Monkeys
 (D) Guinea pigs

 15. Which one of the following cannot convert glucose to Vitamin C?
 (A) Albino rats
 (B) Dogs
 (C) Monkeys
 (D) Cows

16. Transketolase has the coenzyme:
 (A) NAD+
 (B) FP
 (C) TPP
 (D) Pyridoxol phosphate

 17. Two conditions in which gluconeogenesis is increased are
(A) Diabetes mellitus and atherosclerosis
(B) Fed condition and thyrotoxicosis
(C) Diabetes mellitus and Starvation
(D) Alcohol intake and cigarette smoking

 18. Acetyl CoA is not used for the synthesis of
(A) Fatty acid
(B) Cholesterol
(C) Pyruvic acid
(D) Citric acid

19. The total glycogen content of the body is about ______ gms.
(A) 100
(B) 200
(C) 300
(D) 500

20. The total Glucose in the body is ________ gms.
(A) 10–15
(B) 20–30
(C) 40–50
(D) 60–80

21. Pyruvate kinase requires ______ ions for maximum activity.
(A) Na+
(B) K+
(C) Ca2+
(D) Mg2+

22. ATP is ‘wasted’ in Rapoport-Lueberring cycle in RBCs as otherwise it will inhibit
(A) Phosphoglucomutase
(B) Phosphohexo isomerase
(C) Phosphofructo kinase
(D) Phosphoenol pyruvate carboxy kinase

23. The following co-enzyme is needed for the oxidative decarboxylation of ketoacids:
 (A) NADP+
(B) TPP
(C) Folate coenzyme
(D) Biotin coenzyme

 24. Synthesis of Glucose from amino acids is termed as
 (A) Glycolysis
 (B) Gluconeogenesis
 (C) Glycogenesis
 (D) Lipogenesis

 25. The following examples are important heteropolysaccharides except
(A) Amylopectin
(B) Heparin
(C) Peptidoglycan
(D) Hyaluronic acid

 26. Whcih of the following features are common to monosaccharides?
(A) Contain asymmetric centres
(B) Are of 2 types – aldoses and ketoses
(C) Tend to exist as ring structures in solution
(D) Include glucose, galactose and raffinose

27. Polysaccharides
(A) Contain many monosaccharide units which may or may not be of the same kind
(B) Function mainly a storage or structural compounds
(C) Are present in large amounts in connective tissue
(D) All of these

 28. The absorption of glucose in the digestive tract
(A) Occurs in the small intestine
(B) Is stimulated by the hormone Glucagon
(C) Occurs more rapidly than the absorption of any other sugar
(D) Is impaired in cases of diabetes mellitus

29. UDP-Glucose is converted to UDPGlucuronic acid by
(A) ATP
(B) GTP
(C) NADP+
(D) NAD+

 30. The enzymes involved in Phosphorylation of glucose to glucose 6- phosphate are
(A) Hexokinase
(B) Glucokinase
(C) Phosphofructokinase
(D) Both (A) and (B)

31. In conversion of Lactic acid to Glucose, three reactions of Glycolytic pathway are circumvented, which of the following enzymes do not participate?
(A) Pyruvate Carboxylase
(B) Phosphoenol pyruvate carboxy kinase
(C) Pyruvate kinase
(D) Glucose-6-phosphatase

32. The normal resting state of humans, most of the blood glucose burnt as “fuel” is consumed by (A) Liver
(B) Brain
(C) Kidneys
(D) Adipose tissue

 33. A regulator of the enzyme Glycogen synthase is
(A) Citric acid
(B) 2, 3 bisphosphoglycerate
(C) Pyruvate
(D) GTP

34. Which of the following compound is a positive allosteric modifier of the enzyme pyruvate carboxylase?
(A) Biotin
(B) Acetyl CoA
(C) Oxaloacetate
(D) ATP

 35. A specific inhibitor for succinate dehydrogenase is
 (A) Arsinite
 (B) Melouate
 (C) Citrate
 (D) Cyanide

 36. Most of the metabolic pathways are either anabolic or catabolic. Which of the following pathways is considered as “amphibolic” in nature?
 (A) Glycogenesis
 (B) Glycolytic pathway
 (C) Lipolysis
 (D) TCA cycle

 37. Transketolase activity is affected in
(A) Biotin deficiency
(B) Pyridoxine deficiency
(C) PABA deficiency
(D) Thiamine deficiency

 38. The following metabolic abnormalities occur in Diabetes mellitus except
 (A) Increased plasma FFA
 (B) Increased pyruvate carboxylase activate
 (C) Decreased lipogenesis
 (D) Decreased gluconeogenesis

 39. A substance that is not an intermediate in the formation of D-glucuronic acid from glucose is   (A) Glucoss-1-p
 (B) 6-Phosphogluconate
 (C) Glucose-6-p
 (D) UDP-Glucose

40. The hydrolysis of Glucose-6-P is catalysed by a phosphatase that is not formed in which of the following?
 (A) Liver
 (B) Kidney
 (C) Muscle
 (D) Small intestine

41. An essential for converting Glucose to Glycogen in Liver is
(A) Lactic acid
(B) GTP
(C) CTP
(D) UTP



42. For glycogenesis, Glucose should be converted to
(A) Glucuronic acid
(B) Pyruvic acid
(C) UDP glucose
(D) Sorbitol

43. Fluoride inhibits ______ and arrests glycolysis.
(A) Glyceraldehyde-3-phosphate dehydrogenase
(B) Aconitase
(C) Enolose
(D) Succinate dehydrogenase