19. Chose the reaction of glycolysis catalyzed by an enzyme phosphofructokinase:

1. Production of fructose-1,6-bisphosphate

2. Production of glucose-6-phosphate

3. Production of fructose 1-phosphate

4. Production of dihyroxyacetone phosphate

5. Production of 1,3-bisphosphoglycerate

20. In glycolytic pathway all the substances are formed EXEPT:

A. acetyl-CoA

B. glyceraldehydes –3-phosphate

C. phosphoenol pyruvate

D. adenosine diphosphate

E. Fructose-bis-phosphate

21. Glycolysis is also referred to as:

A. Embden-Meyerhof-Parnas pathway

B. Lineweaver-Burk pathway

C. Krebs-Henseleit pathway

D. Watson-Crick pathway

E. Chargaff pathway

22. Which of the following is a substrate for aldolase activity in Glycolytic pathway?

1. Fructose1,6-bisphosphate

2. Glyceraldehyde-3-phosphate

3. Glucose-6-phosphate

4. Fructose-6-phosphate

5. Glucose1, 6-bisphosphate

23. Which of the following enzyme-catalysed reactions has a product containing a newly formed high energy phosphate bond?

1. 2-phosphoglycerate to phosphoenolpyruvate

2. The phosphorylation of glucose

3. Fructose 1,6-bisphosphate to glyceraldehydes-3-phosphate and dihydroxyacetone phosphate

4. 3-phosphoglycerate to 2-phosphoglycerate

5. Dihydroxyacetone phosphate to glyceraldehydes phosphate

24. Glycolysis is mainly regulated by:

1. Phosphofructokinase

2. Enolase

3. glyceraldehydes-3-phosphate dehydrogenase

4. Aldolase

5. All of these

25. Pyruvate kinase requires __ ions for maximum activity.

1. Mg²⁺

2. Mn²⁺

3. Fe²⁺

4. Br^-

5. Cl^-

26. Glucokinase can be characterized by one of the following statements:

A. It has a much higher Michaelis constant (K_m) for glucose than does hexokinase

B. It is the major regulatory enzyme of glycolysis

C. ATP is an activator of this enzyme

D. It is located in mitochondria

E. The reaction that is catalysed by this enzyme produces a high energy phosphate

27. One mole of glucose in glycolytic pathway in anaerobic conditions produces:

A. two moles of lactate

B. five moles of lactate

C. three moles of lactate

D. four moles of lactate

E. one mole of lactate

28. Lactate dehydrogenase is an oligomeric molecule which contains how many number of subunits:

1. Four

2. Two

3. Three

4. Six

5. Eight

29. The predominant products of starch hydrolysis by amylase are:

1. Maltose, maltotriose and limit dextrins

2. Maltose, lactose and limit dextrins

3. Maltotriose, limit dextrins and glucose

4. Glucose, maltose and maltotriose

5. Lactose, sucrose and maltose

30. Glycolysis proceeds in:

A. cytoplasm of every living cell

B. cytoplasm of red blood cell only

C. mitochondria of striated muscle cell

D. nuclei of liver cells

E. Lysosomal vesicles

31. Excessive intake of ethanol increases the ratio:

1. NADH/NAD⁺

2. NAD⁺ /NADH

3. FADH₂/ FAD

4. FAD/FADH₂

5. NADPH/NADP+

32. In glycolysis ATP is produced by the process of:

A. Substrate phosphorylation

B. Photosynthetic phosphorylation

C. Transfer of phosphate group from fructose-biphosphate upon ADP

D. oxidative phosphorylation

33. Conversion of glucose to glucose-6- phosphate in human liver is catalyzed by:

1. Glucokinase only

2. Hexokinase only

3. Hexokinase and glucokinase

4. Glucose-6-phosphate dehydrogenase

5. Glucophosphatase

34. As a result of anaerobic glycolysis glucose is converted to:

A. Lactic acid

B. Glycogen

C. Citric acid

D. Succinic acid

E. Acetoacetic acid

35. The following is an enzyme required for glycolysis:

1. Pyruvate kinase

2. Pyruvate dehydrogenase

3. Pyruvate carboxylase

4. Glucose-6-phosphatose

5. Glycerokinase

36. What is the net production of high energy phosphate bonds in anaerobic glycolysis?

A. 2 moles

B. 4 moles

C. 6 moles

D. 8 moles

E. 10 moles

37. When O₂ supply is inadequate, pyruvate is converted to:

1. Lactate

2. Phosphopyruvate

3. Acetyl CoA

4. Alanine

5. Citrate

38. UDP-Glucose is converted to UDP-Glucuronic acid by:

1. NAD⁺

2. ATP

3. GTP

4. NADP⁺

5. FAD

39. Biosynthesis of the purine ring occurs owing to ribose-5-phosphate by gradual joining of nitrogen and carbon atoms inside the heterocycle structure and closing of the rings. The metabolic source of ribose-5-phosphate is:

A. Pentose phosphate pathway.

B. Glycolysis.

C. Glycogenosis.

D. Gluconeogenesis.

E. Glycogcnolysis.

40. Which of the following compound is a positive allosteric modifier of the enzyme pyruvate carboxylase?

1. Acetyl CoA

2. Biotin

3. Oxaloacetate

4. ATP

5. AMP

41. Galactose is phosphorylated by galactokinase to form:

1. Galactose-1-phosphate

2. Galactose-6-phosphate

3. Galactose-1, 6 diphosphate

4. All of these

42. Individuals who eat fresh fava beans are protected to a certain extent from malaria. Which enzyme deficiency takes place under these conditions?

1. Glucose-6-phosphate dehydrogenase

2. Transaldolase

3. Ribulosephoshateisomerase

4. Pyruvate dehydrogenase

5. Transketoase

43. In a patient pain along great nerve trunks is observed as well as increase of pyruvate in blood. Insufficiency of what vitamin may cause these symptoms?

1. Vitamin B₁

2. Vitamin C

3. Vitamin B₆

4. Vitamin K.

5. Vitamin PP

44. The pentose phosphate pathway sometimes is referred to as:

A. Hexose monophosphate shunt

B. Hexose bisphosphate shunt

C. Chargaff pathway

D. Krebs-Henseleit pathway

E. Embden-Meyerhof-Parnas pathway

45. In the tricarboxylic acid cycle (TCA) are oxidized:

1. Acetyl-CoA

2. Pyruvate

3. Lactate

4. Glucose

5. Fructose

46. Two important byproducts of pentose phosphate pathway are:

1. NADPH and pentose

2. NADH and pentose sugars

3. Pentose and 4 membered sugars

4. Pentose and sedoheptulose

5. Glucose and NADH

47. Lipoic acid is a cofactor of the next enzyme complex:

1. Pyruvate dehydrogenase

2. Lactate dehydrogenase

3. Succinate dehydrogenase

4. Cytochrome oxidase

5. Transketolase

48. Which of the following metabolite integrates glucose and fatty acid metabolism?

1. Acetyl CoA

2. Pyruvate

3. Citrate

4. Lactate

5. Glucose

49. Pyruvate dehydrogenase complex and α-ketoglutarate dehydrogenase complex require the following for their oxidative decarboxylation:

1. CoASH, TPP,NAD+,FAD, Lipoate

2. CoASH and lipoic acid

3. NAD+ and FAD

4. CoASH and TPP

5. TPP

50. The following enzyme is required for the hexose monophosphate shunt pathway:

1. Glucose-6-phosphate dehydrogenase

2. Glucose-6-phosphatase

3. Phosphorylase

4. Aldolase

5. Phosphofructokinase

51. UDP Glucuronic acid is required for the biosynthesis of:

1. Glycogen

2. Lactose

3. Starch

4. Chondroitin sulphates

5. pyruvate

55. Our body can get pentoses from:

1. HMP shunt

2. Glycolytic pathway

3. Uromic acid pathway

4. TCA cycle

5. Gluconeogenesis

56. Which from listed below pathways is responsible for the synthesis of ribose-5-phosphate, a component of nucleic acids:

A. pentose phosphate pathway

B. glycolysis

C. Oxidative decarboxylation of pyruvate

D. Krebs cycle

E. Embden-Meyerhof-Parnas pathway

57. Transketolase (one of enzymes of pentose phosphate pathway) contains as coenzyme:

1. TPP

2. Tocoferol

3. Pyridoxine

4. NAD

5. Folic acid

58. Which of the following substances inhibit pentose phosphate pathway?

1. NADHPH

2. ADP

3. FAD

4. NAD⁺

5. Mg²

59. Pyruvate dehydrogenase complex contains derivatives of the following vitamins:

1. Lipoic acid

2. Pyridoxine

3. Cyanocobalamine

4. Retinol

5. Ubiquinone

60. Dehydrogenase enzymes of the hexose-monophosphate shunt are

1. NADP⁺ specific

2. NAD⁺ specific

3. FAD specific

4. FMN specific

5. Biotin specific

61. There are several pathways for glucose transformation and utilization, one of them is pentose phosphate pathway, which actively proceeds in liver, adrenal cortex, red blood cells. What is the main aim of this pathway?

1. NADPH₂ generation and production of pentoses

2. NADH₂ and gluconioc acid production

3. FADH₂ generation

4. Synthesis of glycogen and fat

5. Acetyl-CoA production

62. Oxidative decarboxylation of pyruvate requires

1. CoASH

2. NADP⁺

3. Cytichromes

4. Pyridoxal phosphate

5. Biotin

63. The next product is formed during oxidative decarboxylation of pyruvate?

A. Acetyl-CoA

B. Acyl-CoA

C. Oxaloacetic acid

D. Lactic acid

E. Succinyl-CoA

64. Which from listed below vitamins is involved in the oxidative decarboxylation of pyruvate?

1. Lipoic acid

2. Tocoferol

3. Pyridoxine

4. Ascorbic acid

5. Folic acid

65. Before pyruvic acid enters the TCA cycle it must be converted to:

1. Acetyl CoA

2. Lactate

3. α-ketoglutarate

4. Citrate

5. Glucose

66. The oxidative phase of pentose phosphate pathway is very active in red blood cells and hepatocytes. Which of the following is the end product of this phase?

1. Ribulose-5-phoshate

2. 6-Phospho-gluconate

3. Pyruvate

4. Glyceraldehyde-3-phosphate

5. Fructose-6-phoshate

67. Which of the following enzymes catalyze reaction: Fructose+ATP → Fructose-1-phosphate + ADP:

1. Fructokinase

2. Galactokinase

3. Hexokinase

4. Glucokinase

5. pyruvate kinase

68. Which one of the following is a rate limiting enzyme of gluconeogenesis?

1. Pyruvate carboxylase

2. Hexokinase

3. Phsophofructokinase

4. Pyruvate kinase

5. Phosphoglucomutase

69. Reactions of synthesis and degradation of glycogen in cells are regulated by phosphorylation of the next key enzymes of glycogen metabolism:

1. Glycogen synthase and glycogen phosphorylase

2. Glycogen phosphorylase and lipase

3. Glycogen synthase and protein kinase

4. Phosphoprotein phosphatase and protein kinase

5. Adenilate cyclase and lipase

70. Phosphorolysis of carbohydrates plays a key role in a mobilization of polysaccharides. Under the action of phosphorylase from glycogen is produced by the next substance:

1. Glucose -1-phosphate

2. Glucose 1,6-bis-phosphate

3. Glucose 6-phosphate

4. Glucose

5. Fructose 6-phosphate

71. Glycogen synthesis takes place under the action of several enzymes. Indicate, what enzyme provides the formation of 1,6-glycosidic bonds in glycogen molecule?

1. Glycosyl 4,6-transglycosidase

2. Glycogen synthase

3. Hexokinase

4. Glucokinase

5. Glucose 1-phosphate uridil transferase

72. Insulin exhibits the next effect on glycogen metabolism:

1. Stimulation of glycogen breakdown by activation of phosphorylase

2. Inhibition of glycogenolysis by suppression of phosphorylase

3. Stimulation of glycogenesis by activation of glycogen synthase

4. Stimulation of glycogen utilization in muscle cells

5. Suppression of glycogen breakdown by inhibition of debranching enzyme.

73. Glycogen synthase is characterized by all of the following statements EXEPT:

A. It is activated by phosphorylation

B. Its substrate is uridine diphosphate glucose

C. The enzyme exists in active and inactive forms

D. It requires the primer strand of glycogen

E. It is found in association with glycogen granules

74. The greatest quantity of the body glycogen can be found in which of the following human tissue?