MCQs on VITAMINS

1. Retinol and retinal are interconverted requiring dehydrogenase or reductase in the

2. Vitamin A or retinol is a
A. Benzoquinone derivative
B. 6-Hydroxychromane
C. Polyisoprenoid compound containing a cyclohexenyl ring
D. Steroid
3. The recommended daily allowance of Vitamin A for an adult is
A. 5000 I.U.
B. 3000 I.U.
C. 2500 I.U.
D. 1000 I.U.
4. Preformed Vitamin A is supplied by
A. Milk , fat and liver
B. All yellow fruits
C. All yellow vegetables
D. Leafy green vegetables
5. Vitamins are
A. Accessory food factors
B. Generally synthesized in the body
C. Proteins in nature
D. Produced in endocrine glands
6. b – Carotene , precursor of Vitamin A , is oxidatively cleaved by
A. b – Carotene dioxygenase
B. Hydroxylase
C. Transferase
D. Oxygenase
7. Retinal is reduced to retinol in intestinal mucosa by a specific retinaldehyde
reductase utilizing
A. NADPH + H+
B. NAD
C. FAD
D. NADH + H+
8. The international unit of Vitamin A is equivalent to the activity caused by
A. 1.0 µg of vitamin A alcohol
B. 0.6 µg of vitamin A alcohol
C. 0.344 µg of vitamin A alcohol
D. 0.3 µg of vitamin A alcohol
9. The normal serum concentration of vitamin A in mg/100 ml is
 A. 0-5
B. 100-150
C. 15-60
D. 5-10
10. Lumirhodopsin is stable only at temperature below
A. – 10O C
B. - 20 O C
C. -50 O C
D. -40 O C
11. Retinol is transported in blood bound by
A. Aproretinol binding protein
B. a2 – Globulin
C. Albumin
D. b – Globulin
12. One manifestation of vitamin A deficiency is
A. Loss of hair
B. Painful joints
C. Night blindness
D. Thickening of long bones
13. An important function of vitamin A is
A. To play an integral role in protein synthesis
B. To act as coenzyme for a few enzymes
C. To maintain the integrity of epithelial tissue
D. To prevent hemorrhages
14. Deficiency of vitamin A causes
A. Xeropthalmia
B. Megaloblastic anemia
C. Pernicious anemia
D. Hypoprothrombinemia
15. Retinal is a component of
A. Iodopsin
B. Cardiolipin
C. Rhodopsin
D. Glycoproteins
16. On exposure to light rhodopsin forms
A. All trans-retinal
B. Cis- retinal
C. Retinoic acid
D. Retinol
17. Carr- Price reaction is used to detect
A. Vitamin D
B. Vitamin A
C. Ascorbic acid
D. Vitamin E
18. Retinoic acid participates in the synthesis of
A. Iodopsin
B. Cardiolipin
 C. Glycoprotein
D. Rhodopsin
19. Vitamin D absorption is increased in
A. Acid pH of intestine
B. Impaired fat absorption
C. Contents of diet
D. Alkaline pH of intestine
20. The most potent vitamin D metabolite is
A. 24,25- Dihydroxycholecalciferol
B. 7- Dehydrocholestrol
C. 1,25- Dihydroxycholecalciferol
D. 25-Hydroxycholecalciferol
21. The structure shown below is of

A. 25- Hydroxycholecalciferol
B. Cholecalciferol
C. 7-Dehydrocholesterol
D. Ergocalciferol
22. The normal serum concentration of 25- hydroxycholecalciferol in ng/ml is
A. 8-55
B. 100-150
C. 60-100
D. 0-8
23. A poor source of vitamin D is
A. Butter
B. Egg
C. Milk
D. Liver
24. The normal serum concentration of 1,25 – dihydroxycholecalciferol in pg/ml is
A. 80-100
B. 5-20
C. 1-5
D. 26-65
25. The normal serum concentration of 24,25 – dihydroxycholecalciferol in ng/ml is
A. 60-100
B. 1-5
 C. 25-50
D. 8-20
26. Deficiency of vitamin D causes
A. Ricket and osteomalacia
B. Hypothyroidism
C. Tuberculosis of bones
D. Skin cancer
27. Richest source of vitamin D is
A. Fish liver oils
B. Egg yolk
C. Butter
D. Margarine
28. The b-ring of 7-dehydrocholesterol is cleaved to form cholecalciferol by
A. Dim light
B. Infrared light
C. Ultraviolet irridation with sunlight
D. Light of tube lights
29. One international unit (I.U.) of vitamin D is defined as the biological activity of
A. 0.025 µg of ergocalciferol
B. 0.025 µg of ergosterol
C. O.025 µg of 7-dehydrocholecalciferol
D. 0.025 µg of cholecalciferol
30. Insignificant amount of vitamin E is present in
A. Fish liver oil
B. Safflower seed oil
C. Sunflower seed oil
D. Wheat germ oil
31. The requirement of vitamin E is increased with great intake of
A. Saturated fat
B. Polyunsaturated fat
C. Proteins
D. Carbohydrates
32. The activity of tocopherols is destroyed by
A. Commercial cooking
B. Conjugation
C. Reduction
D. All of the above
33. Calcitriol synthesis involves
A. Both liver and kidney
B. Adipose tissue
C. Intestine
D. Muscle
34. Vitamin E reduces the requirement of
A. Zinc
B. Iron
C. Selenium
D. Magnesium
35. Tocopherols prevent the oxidation of
A. Vitamin A
B. Vitamin K
C. Vitamin D
D. Vitamin C
36. The most important natural antioxidant is
A. Vitamin D
B. Vitamin K
C. Vitamin E
D. Vitamin B12
37. Vitamin K is found in
A. Meat
B. Fish
C. Milk
D. Green leafy plants
38. Absorption of vitamin K requires normal absorption of
A. Glucose
B. Calcium
C. Fat
D. Amino acids
39. All the following conditions produce a real or functional deficiency of vitamin K
except
A. Being a new born infant
B. Total lack of red meat in the diet
C. Prolonged oral, broad spectrum antibiotic therapy
D. The total lack of green leafy vegetables in the diet
40. Creatinuria is caused due to the deficiency of vitamin
A. D
B. K
C. E
D. A
41. Vitamin K2 was originally isolated from
A. Putrid fish meal
B. Alfa Alfa
C. Wheat germ
D. Soyabean
42. Vitamin K is involved in posttranslational modification of the blood clotting factors
by acting as cofactor for the enzyme
A. Oxidase
B. Hydroxylase
C. Decarboxylase
D. Carboxylase
43. Vitamin synthesised by bacteria in the intestine is
A. K
B. D
C. C
D. A
44. Vitamin K is a cofactor for
A. Synthesis of tryptophan
B. Formation of - amino butyrate
C. b-Oxidation of fatty acid
D. Gamma carboxylation of glutamic acid residue
45. Dicoumarol is antagonist to
A. Tocopherol
B. Riboflavin
C. Retinol
D. Menadione
46. The structure shown below is of

A. Ascorbic acid
B. a– D- glucopyranose
C. b-a - Glucopyranose
D. Saccharo lactone
47. Hypervitaminosis K in neonates may cause
A. Pellagra
B. Jaundice
C. Porphyria
D. Prolonged bleeding
48. The structure shown below is of

A. Biotin
B. Pyridoxine
C. Thiamin
D. Rivoflavin
49. In the individuals who are given liberal quantities of vitamin C , the serum ascorbic
acid level is
A. 10-20 µg/100ml
 B. 1-10 µg/100 ml
C. 2-4 µg/100ml
D. 1-1.4µg/100ml
50. Ascorbic acid can reduce
A. 2,4 – Dinitrobenzene
B. 2,6 – Dichlorophenol indophenol
C. 2,6 – Diiodoxypyridine
D. 2,6 - Dibromobenzene
51. The vitamin which would most likely become deficient in an individual who develop
a completely carnivorous life style is
A. Cobalamine
B. Thiamin
C. Vitamin C
D. Niacin
52. Vitamin required in conversion of folic acid to folinic acid is
A. Niacin
B. Biotin
C. Cobalamin
D. Ascorbic acid
53. In human body highest concentration of ascorbic acid is found
A. Spleen
B. Adrenal cortex
C. Adrenal medulla
D. Liver
54. Vitamin required for the conversion of p- hydroxyphenylpyruvate to homogentisate
is
A. Ascorbic acid
B. Folacin
C. Cobalamin
D. Biotin
55. The vitamin required for the formation of hydroxyproline (in collagen ) is
A. Vitamin E
B. Vitamin D
C. Vitamin A
D. Vitamin C
56. Sterlised milk lacks in
A. Vitamin D
B. Vitamin A
C. Vitamin C
D. Thiamin
57. The vitamin B1 coenzyme ( TPP) is involved in
A. Oxidative decarboxylation
B. Transamination
C. Carboxylation
D. Hydroxylation
58. Scurvy is caused due to the deficiency of
A. Vitamin A
 B. Vitamin K
C. Vitamin D
D. Vitamin C
59. The vitamin B1 deficiency causes
A. Ricket
B. Beriberi
C. Pellagra
D. Nyctalopia
60. Both Wernicke’s disease and beriberi can be reversed by administrating
A. Pyridoxine
B. Vitamin B12
C. Thiamin
D. Retinol
61. Increased glucose consumption increases the dietary requirement for
A. Niacin
B. Pyridoxine
C. Biotin
D. Thiamin
62. Concentration of pyruvic acid and lactic acid in blood is increased due to deficiency
of the vitamin
A. Thiamin
B. Niacin
C. Riboflavin
D. Pantothenic acid
63. Thiamin is oxidised to thiochrome in alkaline solution by
A. Potassium chlorate
B. Potassium dichromate
C. Potassium permanganate
D. Potassium ferricyanide
64. The pellagra preventive factor is
A. Riboflavin
B. Pyridoxine
C. Niacin
D. Pantothenic acid
65. Riboflavin deficiency causes
A. Cheilosis
B. Mental deterioration
C. Dermatitis
D. Loss of weight
66. The daily requirement of riboflavin for adult in mg is
A. 4.0 – 8.0
B. 1.2 – 1.7
C. 0 – 1.0
D. 2.0 – 3.5
67. Riboflavin is a coenzyme in the reaction catalysed by the enzyme
A. b– Hydroxy acyl CoA
B. Acyl CoA dehydrogenase
 C. Acyl CoA synthetase
D. Enoyl CoA dehydrogenase
68. Magenta tongue is found in the deficiency of the vitamin
A. Riboflavin
B. Nicotinic acid
C. Pyridoxine
D. Thiamin
69. In new born infants phototherapy may cause hyperbilirubinemia with deficiency of
A. Thiamin
B. Riboflavin
C. Pantothenic acid
D. Ascorbic acid
70. Corneal vascularisation is found in deficiency of the vitamin
A. B6
B. B3
C. B2
D. B1
71. Pellagra is caused due to the deficiency of
A. Pantothenic acid
B. Ascorbic acid
C. Pyridoxine
D. Niacin
72. Niacin is synthesised in the body from
A. Tryptophan
B. Glutamate
C. Tyrosine
D. Aspartate
73. Niacin is present in maize in the form of
A. Niatin
B. Niacytin
C. Nicotin
D. Nicyn
74. Pellagra occurs in population dependent on
A. Wheat
B. Rice
C. Maize
D. Milk
75. Niacin or nicotinic acid is a monocarboxylic acid derivative of
A. Pyridine
B. Flavin
C. Pyrimidine
D. Adenine
76. The proteins present in maize are deficient in
A. Tyrosine
B. Threonine
C. Tryptophan
D. Lysine
77. The enzymes with which nicotinamide act as coenzyme are
A. Dehydrogenases
B. Decarboxylases
C. Transaminases
D. Carboxylases
78. In body of 1 mg of niacin can be produced from
A. 30 mg of tryptophan
B. 30 mg of pantothenic acid
C. 60 mg of tryptophan
D. 60 mg of pyridoxine
79. Daily requirement of niacin for the adult male is
A. 30-40 mg
B. 5-8 mg
C. 16-20 mg
D. 12-15 mg
80. The precursor of CoA is
A. Pantothenate
B. Thiamin
C. Pyridoxamine
D. Riboflavin
81. “Burning foot syndrome” has been ascribed to the deficiency
A. Pantothenic acid
B. Cobalamin
C. Thiamin
D. Pyridoxine
82. The vitamin which does not contain a ring in the structure is
A. Pantothenic acid
B. Riboflavin
C. Vitamin D
D. Thiamin
83. Pantothenic acid is a constituent of the coenzyme involved in
A. Oxidation
B. Decarboxylation
C. Acetylation
D. Dehydrogenation
84. Pyridoxal phosphate is central to
A. Amidation
B. Deamination
C. Carboxylation
D. Transamination
85. The vitamin required as coenzyme for the action of transaminases is
A. Niacin
B. Riboflavin
C. Pyridoxal phosphate
D. Pantothenic acid
86. Vitamin B6 deficiency may occur during therapy with
A. Isoniazid
 B. Sulpha drugs
C. Terramycin
D. Aspirin
87. Epileptiform convulsion in human infants have been attributed to the deficiency of
the vitamin
A. B12
B. B2
C. B6
D. B1
88. Biotin is a coenzyme of the enzyme
A. Carboxylase
B. Decarboxylase
C. Hydroxylase
D. Deaminase
89. ‘Xanthurenic acid index ‘ is a reliable criterion for the deficiency of the vitamin
A. Pyridoxal
B. Pantothenic acid
C. Cobalamin
D. Thiamin
90. Deficiency of vitamin B6 may occur in
A. Obese person
B. Thin person
C. Alcoholics
D. Diabetics
91. In biotin-containing enzymes, the biotin is bound to the enzyme by
A. A covalent bond with CO2
B. An amide linkage to carboxyl group of glutamine
C. An amide linkage to an amino group of lysine
D. An amide linkage to a– carboxyl group of protein
92. The coenzyme required for conversion of pyruvate to oxaloacetate is
A. FAD
B. TPP
C. NAD
D. Biotin
93. A molecule of CO2 is captured by biotin when it acts as coenzyme for carboxylation
reaction . The carboxyl group is covalently attached to
A. A nitrogen (N1) of the biotin molecule
B. a – Amino group of lysine
C. a– Amino group of protein
D. Sulphur of thiopene ring
94. Empirical formula of cobalamin is
A. C63 H88 N14 O14 P.CO
B. C61 H88 N12 O14 P.CO
C. C61 H82 N12 O12 P.CO
D. C63 H88 N12 O14 P.CO
95. Consumption of raw eggs can cause deficiency of
A. Biotin
 B. Riboflavin
C. Pantothenic acid
D. Thiamin
96. A cofactor required in oxidative decarboxylation of pyruvate is
A. Lipoate
B. Pantothenic acid
C. Biotin
D. Para aminobenzoic acid
97. The cofactor or its derivative required for the conversion of acetyl- CoA to malonyl-
CoA is
A. NAD+
B. FAD
C. ACP
D. Biotin
98. The central heavy metal cobalt vitamin B12 is co-ordinately bound to
A. Cyanide group
B. Carboxyl group
C. Amino group
D. Sulphide group
99. Vitamin B12 has a complex ring structure ( corrin ring ) consisting of four
A. Purine rings
B. Pyrrole rings
C. Pyrimidine rings
D. Pteridine rings
100.The central structure of B12 referred to as corrin ring system consists of
A. Cobalt
B. Magnesium
C. Manganese
D. Iron
101. A deficiency of vitamin B12 causes
A. Beri – Beri
B. Ricket
C. Pernicious anemia
D. Scurvy
102. Vitamin required for metabolism of diols eg. Conversion of ethylene glycol to
acetaldehyde is
A. Thiamin
B. Pyridoxine
C. Cobalamin
D. Folic acid
103. Both folic acid and methyl cobalamin (Vitamin B12 ) are required in
A. Deamination of threonine
B. Conversion of pyridoxal phosphate to pyridoxamine phosphate
C. Deamination of serine
D. Methylation of homocysteine to methionine
104. Subacute combined degeneration of cord is caused due to deficiency of
A. Biotin
 B. Cobalamin
C.Thiamin
D.Niacin
105. Folic acid or folate consists of the
A. Base pteridine, p- amino benzoic acid and aspartate
B. Base purine , p-hydroxy benzoic acid and glutamate
C. Base pteridine , p- amino benzoic acid and glutamate
D. Base purine , p- amino benzoic acid and glutamate
106. Vitamin B12 deficiency can be diagnosed by urinary excretion of
A. Malate
B. Lactate
C. Methylmalonate
D. Pyruvate
107. Folate as a coenzyme is involved in the transfer and utilisation of
A. Amino group
B. Amido group
C. Single carbon moiety
D. Hydroxyl group
108. Folate deficiency causes
A. Hemolytic anemia
B. Microcytic anemia
C. Megaloblastic anemia
D. Iron deficiency anemia
109. Sulpha drugs interfere with bacterial synthesis of
A. Vitamin E
B. Lipoate
C. Tetrahydrofolate
D. Ascorbic acid
110. Folic acid deficiency can be diagnosed by increased urinary excretion of
A. Cystathionine
B. Figlu
C. Methylmalonate
D. Creatinine

ANSWERS

1. A
2. C
3. A
4. A
5. A
6. A
7. A
8. D
9. C
10. C
11. A
12. C
13. C
14. A
15. C
16. A
17. B
18. C
19. A
20. C
21. B
22. A
23. C
24. D
25. B
26. A
27. A
28. C
29. D
30. A
31. B
32. A
33. A
34. C
35. A
36. C
37. D
38. C
39. B
40. C
41. A
42. D
43. A
44. D
45. D
46. A
47. B
48. C
49. D
50. B
51. C
52. D
53. B
54. A
55. D
56. C
57. A
58. D
59. B
60. C
61. D
62. A
63. D
64. C
65. A
66. B
67. B
68. A
69. B
70. C
71. D
72. A
73. B
74. C
75. A
76. C
77. A
78. C
79. C
80. A
81. A
82. A
83. C
84. D
85. C
86. A
87. C
88. A
89. A
90. C
91. C
92. D
93. A
94. A
95. A
96. A
97. D
98. A
99. B
100. A
101. C
102. C
103. D
104. C
105. C
106. C
107. C
108. C
109. C
110. B