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VITAMINS- Part 7
See all quizzes of VITAMINS- Part 7 here:
1 When light falls on rod cells
(A) All-cis-retinal is converted into all-trans-retinal
(B) 11-cis-retinal is converted into 11-trans-retinal
(C) 11-trans-retinal is converted into all-transretinal
(D) 11-cis-retinal is converted into all-trans-retinal
2. Conversion of all-trans-retinal into alltrans-
retinol requires
(A) NAD (B) NADH
(C) NADP (D) NADPH
3. Retinol isomerase is present in
(A) Retina (B) Liver
(C) Both (A) and (B) (D) None of these
4. Anti-oxidant activity is present in
(A) β-Carotene (B) Retinol
(C) Retinoic acid (D) All of these
5. One international Unit of vitamin A is the
activity present in
(A) 0.3 μg of β-Carotene
(B) 0.3 μg of retinol
(C) 0.6 μg of retinoic acid
(D) All of these
6. Daily requirement of vitamin A in an adult
man can be expressed as
(A) 400 IU (B) 1,000 IU
(C) 5,000 IU (D) 10,000 IU
7. Vitamin B6 includes
(A) Pyridoxal (B) Pyridoxamine
(C) Pyridoxine (D) All of these
8. An early effect of vitamin a deficiency is
(A) Xerophthalmia
(B) Keratomalacia
(C) Prolonged dark adaptation time
(D) Follicular hyperkeratosis
9. Nyctalopia is
(A) Drying of eyes
(B) Destruction of cornea
(C) Blindness
(D) Inability to see in dimlight
10. Rod cells possess a trans-membrane
protein which is
(A) Adenylate cyclase (B) Transducin
(C) Rhodopsin (D) B as well as C
11. Provitamins A include
(A) Retinal (B) Retionic acid
(C) Carotenes (D) All of these
12. Retinoic acid can
(A) Act as a photo receptor
(B) Support growth and differentiation
(C) Act as an anti-oxidant
(D) None of these
13. Prosthetic group in cone cell phototreceptors
is
(A) Iodine (B) Opsin
(C) 11-cis-retinal (D) all-trans-retinal
14. Retinoic acid is involved in the synthesis
of
(A) Rhodopsin (B) Iodopsin
(C) Porphyrinopsin (D) Glycoproteins
15 Transducin is a
(A) Signal transducer (B) Stimulatory G-protein
(C) Trimer (D) All of these
16. Provitamin D3 is
(A) Cholecalciferol
(B) Ergosterol
(C) 7-Dehydrocholesterol
(D) Ergocaliferol
17. Ergosterol is found in
(A) Animals (B) Plants
(C) Bacteria (D) All of these
18. A provitamin D synthesized in human
beings is
(A) Ergosterol
(B) 7-Dehydrocholesterol
(C) Cholecalciferol
(D) 25-Hydroxycholecalciferol
19. 25-Hydroxylation of vitamin D occurs in
(A) Skin (B) Liver
(C) Kidneys (D) Intestinal mucosa
20. Tubular reabsorption of calcium is
increased by
(A) Cholecalciferol
(B) 25-Hydroxycholecalciferol
(C) Calcitriol
(D) All of these
21. Parathormone is required for the conversion
of
(A) Cholecalciferol into 1-hydroxycholecalciferol
(B) Cholecalciferol into 25-hydroxycholecalciferol
(C) 25-Hydroxycholecalciferol into calcitriol
(D) Cholesterol into 7-dehydrocholesterol
22. Calcitriol inhibits the conversion of
(A) Cholesterol into 7-dehydrocholesterol
(B) Cholecalciferol into 1-hydroxycholecalciferol
(C) Cholecalciferol into 25-hydroxycholecalciferol
(D) 25-Hydroxycholecalciferol into 1,25- dihydroxycholecalciferol
23. Bowlegs and knock-knees can occur in
(A) Rickets (B) Osteomalacia
(C) Both A and B (D) Hypervitaminosis D
24. Calcification of soft tissues can occur in
(A) Osteomalacia
(B) Rickets
(C) Hypervitaminosis D
(D) None of these
25. Levels of serum calcium and inorganic
phosphorus are increased in
(A) Hypervitaminosis D
(B) Hypoparathyroidism
(C) Hypovitaminosis D
(D) None of these
26. Requirement of vitamin E increases with
the increasing intake of
(A) Calories (B) Proteins
(C) PUFA (D) Cholesterol
27. In human beings, vitamin E prevents
(A) Sterility
(B) Hepatic necrosis
(C) Muscular dystrophy
(D) None of these
28. Vitamin E protects
(A) Polyunsaturated fatty acids against
aperoxidation
(B) Vitamin A and carotenes against oxidation
(C) Lung tissue against atmospheric pollutants
(D) All of these
29. Intestinal bacteria can synthesise
(A) Phyllogquinone (B) Farnoquinone
(C) Both (A) and (B) (D) Menadione
30. A water soluble form of vitamin K is
(A) Phylloquinone (B) Farnoquinone
(C) Menadione (D) None of these
