Multiple choice questions on vitamins | Biochemistry,

 

1. Vitamins are
(A) Accessory food factors                      (B) Generally synthesized in the body
(C) Produced in endocrine glands            (D) Proteins in nature
2. Vitamin A or retinal is a
(A) Steroid                                                (B) Polyisoprenoid compound containing a cyclohexenyl ring
(C) Benzoquinone derivative                    (D) 6-Hydroxychromane
3. β-Carotene, precursor of vitamin A, is oxidatively cleaved by
(A) β-Carotene dioxygenase                    (B) Oxygenase
(C) Hydroxylase                                       (D) Transferase
4. Retinal is reduced to retinol in intestinal mucosa by a specific retinaldehyde reductase utilising

(A) NADPH + H+ (C) NAD

(B) FAD (D) NADH + H+

5. Preformed Vitamin A is supplied by
(A) Milk, fat and liver
(B) All yellow vegetables
(C) All yellow fruits
(D) Leafy green vegetables

6. Retinol and retinal are interconverted  requiring dehydrogenase or reductase in the presence of

(A) NAD or NADP (C) NADPH

(B) NADH + H+ (D) FAD

7. Fat soluble vitamins are
(A) Soluble in alcohol
(B) one or more Propene units
(C) Stored in liver
(D) All these
8. The international unit of vitamin A is equivalent to the activity caused by
(A) 0.3 µg of Vitamin A alcohol
(B) 0.344 µg of Vitamin A alcohol
(C) 0.6 µg of Vitamin A alcohol
(D) 1.0 µg of Vitamin A alcohol
9. Lumirhodopsin is stable only at temperature below

(A) –10°C (C) –40°C

(B) –20°C (D) –50°C

10. Retinol is transported in blood bound to
(A) Aporetinol binding protein
(B) α2-Globulin
(C) β-Globulin
(D) Albumin

11. The normal serum concentration of vitamin A in mg/100 ml is

(A) 5–10 (C) 100–150

(B) 15–60 (D) 0–5

12. One manifestation of vitamin A deficiency is
(A) Painful joints
(B) Night blindness
(C) Loss of hair
(D) Thickening of long bones
13. Deficiency of Vitamin A causes
(A) Xeropthalmia
(B) Hypoprothrombinemia
(C) Megaloblastic anemia
(D) Pernicious anemia
14. An important function of vitamin A is
(A) To act as coenzyme for a few enzymes
(B) To play an integral role in protein synthesis
(C) To prevent hemorrhages
(D) To maintain the integrity of epithelial tissue
15. Retinal is a component of

(A) Iodopsin (C) Cardiolipin	(B) Rhodopsin (D) Glycoproteins
16. Retinoic acid participates in the synthesis
of: (A) Iodopsin (C) Glycoprotein	(B) Rhodopsin (D) Cardiolipin

17. On exposure to light rhodopsin forms

(A) All trans-retinal (C) Retinol	(B) Cis-retinal (D) Retinoic acid
18. Carr-Price reaction is used to detect
(A) Vitamin A (C) Ascorbic acid	(B) Vitamin D (D) Vitamin E

19. The structure shown below is of
(A) Cholecalciferol
(B) 25-Hydroxycholecalciferol
(C) Ergocalciferol
(D) 7-Dehydrocholesterol
20. Vitamin D absorption is increased in
(A) Acid pH of intestine
(B) Alkaline pH of intestine
(C) Impaired fat absorption
(D) Contents of diet
21. The most potent Vitamin D metabolite is
(A) 25-Hydroxycholecalciferol
(B) 1,25-Dihydroxycholecalciferol
(C) 24, 25-Dihydroxycholecalciferol
(D) 7-Dehydrocholesterol
22. The normal serum concentration of 25-hydroxycholecalciferol in ng/ml is

(A) 0–8 (C) 100–150	(B) 60–100 (D) 8–55
23. The normal serum concentration of 1,25 dihydroxycholecalciferol in pg/ml is
(A) 26–65 (C) 5–20	(B) 1–5 (D) 80–100

24. The normal serum concentration of 24,25- dihydroxycholecalciferol in ng/ml is

(A) 8–20 (C) 1–5	(B) 25–50 (D) 60–100
25. A poor source of Vitamin D is
(A) Egg	(B) Butter

(C) Milk	(D) Liver
26. Richest source of Vitamin D is
(A) Fish liver oils (C) Egg yolk	(B) Margarine (D) Butter

27. Deficiency of vitamin D causes
(A) Ricket and osteomalacia
(B) Tuberculosis of bone
(C) Hypthyroidism
(D) Skin cancer
28. One international unit (I.U) of vitamin D is defined as the biological activity of
(A) 0.025 µg of cholecalciferol
(B) 0.025 µg of 7-dehydrocholecalciferol
(C) 0.025 µg of ergosterol
(D) 0.025 µg of ergocalciferol

29. The β-ring of 7-dehydrocholesterol is cleaved to form cholecalciferol by
(A) Infrared light
(B) Dim light
(C) Ultraviolet irridation with sunlight
(D) Light of the tube lights
30. Calcitriol synthesis involves
(A) Both liver and kidney
(B) Intestine
(C) Adipose tissue
(D) Muscle
31. Insignificant amount of Vitamin E is present in
(A) Wheat germ oil                    (B) Sunflower seed oil
(C) Safflower seed oil                (D) Fish liver oil
32. The activity of tocopherols is destroyed by
(A) Commercial cooking
(B) Reduction
(C) Conjugation
(D) All of these
33. The requirement of vitamin E is increased with greater intake of
(A) Carbohydrates
(B) Proteins
(C) Polyunsaturated fat
(D) Saturated fat
34. Vitamin E reduces the requirement of

(A) Iron (C) Selenium	(B) Zinc (D) Magnesium
35. The most important natural antioxidant
is: (A) Vitamin D (C) Vitamin B12	(B) Vitamin E (D) Vitamin K

36. Tocopherols prevent the oxidation of

(A) Vitamin A (C) Vitamin K	(B) Vitamin D (D) Vitamin C
37. Creatinuria is caused due to the deficiency
of vitamin: (A) A (C) E	(B) K (D) D

38. All the following conditions produce a real or functional deficiency of vitamin K
except:
(A) Prolonged oral, broad spectrum antibiotic therapy
(B) Total lack of red meat in the diet
(C) The total lack of green leafy vegetables in the diet
(D) Being a new born infant
39. Vitamin K is found in
(A) Green leafy plants(B) Meat
(C) Fish (D) Milk
40. Function of Vitamin A:
(A) Healing epithelial tissues
(B) Protein synthesis regulation
(C) Cell growth
(D) All of these
41. Vitamin K2 was originally isolated from:

(A) Soyabean (C) Alfa Alfa	(B) Wheat gram (D) Putrid fish meal
42. Vitamin synthesized by bacterial in the
intestine is: (A) A	(B) C

(C) D	(D) K
43. Vitamin K is involved in posttranslational modification of the blood clotting factors by acting as cofactor for the enzyme:
(A) Carboxylase (C) Hydroxylase	(B) Decarboxylase (D) Oxidase

44. Vitamin K is a cofactor for
(A) Gamma carboxylation of glutamic acid residue
(B) β-Oxidation of fatty acid
(C) Formation of γ-amino butyrate
(D) Synthesis of tryptophan
45. Hypervitaminosis K in neonates may cause

(A) Porphyria (C) Pellagra	(B) Jaundice (D) Prolonged bleeding
46. Dicoumarol is antagonist to
(A) Riboflavin (C) Menadione	(B) Retinol (D) Tocopherol

47. In the individuals who are given liberal quantities of vitamin C, the serum ascorbic
acid level is
(A) 1–1.4 µg/100 ml
(B) 2–4 µg/100 ml
(C) 1–10 µg/100 ml
(D) 10–20 µg/100 ml
48. The vitamin which would most likely become deficient in an individual who
develop a completely carnivorous life style is:

(A) Thiamin (C) Vitamin C

(B) Niacin (D) Cobalamin

49. In human body highest concentration of ascorbic acid is found in:

(A) Liver	(B) Adrenal cortex
(C) Adrenal medulla                       (D) Spleen 50. The vitamin required for the formation of hydroxyproline (in collagen) is:
(A) Vitamin C (C) Vitamin D	(B) Vitamin A (D) Vitamin E

ANSWERS:

1. A 2. B 3. A 4. A 5. A 6. A 7. D 8. A 9. D 10. A 11. B 12. B 13. A 14. D 15. B 16. C 17. A 18. A 19. A 20. A 21. B 22. D 23. A 24. C 25. C 26. A 27. A 28. A 29. C 30. A 31. D 32. A 33. C 34. C 35. B 36. A 37. C 38. B 39. A 40. D 41. D 42. D 43. A 44. A 45. B 46. C 47. A 48. C 49. B 50. A