RRB SCIENCE QUESTIONS

1. Which of the following is not a bone in the
human body?
(a)Sternum
(b) Humerus
(c)Pericardium
(d) Tibia
Ans : c

2. Rennin and lactase, the enzymes required to digest milk, disappear in the human body by the age of
(a) two
(b) three
(c) five
(d) eight
Ans : a

3. Duodenum is situated
(a) at the uppermost part of the small intestine
(b) near the lungs
(c) in the brain
(d) at the tail end of the intestine
Ans : a

4. The heart is covered by a membrane called
(a) Epidermis
(b) Dermis
(c)Epicardium
(d) Pericardium
Ans : d

5. About ……..of the total calcium present in the human body is in the blood.
(a) 99%
(b) 70%
(c) 5%
(d) 1%
Ans : d

6. Phenylketonuria is an example of an inborn error of metabolism. This ‘error’ refers to
(a) hormonal overproduction
(b) non disjunction
(c) atrophy of endocrine glands
(d) inherited lack of an enzyme
Ans : c

7. As in the arms and legs, blood flows against gravity and is prevented from flowing back by
(a) the extremely low pressure of venous blood
(b) valves
(c) movements in the surrounding muscles
(d) the narrowing down of the lumen of veins by the contraction of the muscle layer comprising their walls
Ans : b

8. Identical twins arise when two
(a) cells develop independently from the same zygote
(b) gametes develop independently
(c) sperms develop independently
(d) ova develop independently
Ans : a

9. Element that is not found in blood is
(a)iron
(b) copper
(c)chromium
(d) magnesium
Ans : c

10. Scratching eases itching because
(a) it kills germs.
(b) it suppresses the production of enzymes which cause itching,
(c) it removes the outer dust in the skin.
(d) it stimulates certain nerves which direct the brain to increase the production of antihistaminic chemicals.
Ans : d
11. The gland, which in relation to body size is largest at birth and then gradually shrinks after puberty, is?
(a) Thyroid
(b) Pituitary
(c)Thymus
(d) Adrenal
Ans : c
12. A human sperm may contain ?
1. X-chromosome
2. Y-chromosome
3. XY-chromosome
(a) 1 only
(b) 2 only
(c)1 and 2
(d) l,2 and 3
Ans : c
13. Which of the following is not a bone in the legs
of human body?
(a) Radius
(b) Tibia
(c) Femur
(d) Fibula
Ans : a
14. Bleeding from artery is characterised by which of the following?
1. Blood is red.
2. Blood is purple.
3. Bleeding is continuous.
4. Bleeding is intermittent.
(a)1 and3
(b) 2 and 3
(c)1 and 4
(d) 2 and 4
Ans : b
15. Which of the following is not a vestigial organ?
(a) Centriole
(b) Molar tooth
(c) Appendix
(d) Diaphragm
Ans : d
16. Which of the following bone articulations forms the gliding joint?
(a) Humenis and radius
(b) Carpals
(c) Hip girdle and femur
(d) Skull & neck verterbrae
Ans : b
17. Pancreas secretes hormones which help in
(a) blood clotting
(b) production of antibodies
(c) growth of body
(d) keeping sugar balance in body
Ans : d
18. S-A node of mammalian heart is known as
(a) Autoregulator
(b) Pace-maker
(c) Time controller
(d) Beat regulator
Ans : b
19. Consider the following statements regarding blood pressure:
1. It is the pressure exerted by the blood on the walls of any vessel.
2. It decreases in the arteries as the distance from the heart increases,
3. It is lower in the capillaries than in the arteries.
4. It is usually lower in women than in men.
Of these, the correct ones are
(a)1 and 4
(b) l, 2and 3
(c)2,3 and 4
(d) l,2,3 and 4
Ans : d
20. The hormone responsible for the secretion of milk in mothers, is?
(a) ACTH
(b) Leutinizing hormone
(c) Adrenalin
(d) Lactogenic hormone
21. What is the correct sequence of the following in heart attack?
1. Narrowing of the inner orifice of the vessel
2. ‘Plaque’ from fibrous tissue and high cholesterol
3. Inadequate supply of blood and oxygen
4. Clots of blood carried into the coronary arteries
(a)1,2,3,4
(b) 2,4, 1,3
(c) 2, 3, 1, 4
(d) 4, 2, 1 3
Ans : b
22. Bile juice is secreted by
(a)Pancreas
(b) Liver
(c)Spleen
(d) Gall bladder
Ans : b
23. Veins differ from arteries in having
(a) thinner walls
(b) strong walls
(c) narrower lumen
(d) valves to control direction of flow
Ans : d
24. What is the main function of insulin in the hman body?
(a) To maintain blood pressure
(b) To help in digestion of food
(c) To control the level of sugar in the body
(d) To check the level of iodine in the body
Ans : c
25. An enzyme that works in an acidic medium is
(a) pepsin
(b) tiypsin
(c) ptyalin
(d) maltose
Ans : a
26. The blood pressure is the pressure of blood in
(a)arteries
(b) veins
(c)auricles
(d) ventricles
Ans : a
27. The total number of bones in human skull are
(a) 8
(b) 12
(c) 30
(d) 32
Ans : c
28. Which of the following glands controls the development of sex organs in humans?
(a) Paancreas
(b) Thyroid
(c) Adrenal
(d) Pituitary
Ans : d
29. Oxygen is transported to every cell of the human
body by?
(a)red blood cells
(b) blood platelets
(c)white blood cells
(d) hormones
Ans : a
30. Which of the following components of blood protects human beings from infection?
(a) Plasma
(b) Blood Platelets
(c) Haemoglobin
(d) White Blood Corpuscles
Ans : d
31. The normal temperature of the human body is
(a) 90 F
(b) 98 F
(c) 98.4 F
(d)96.4 F
Ans : c
32 .If a person can see an object clearly when it is placed at distance of about 25 cm away from him, he is suffering from
(a) myopia
(b) hypermetropia
(c) astigmatism
(d) None of these
Ans : d
33. The blood pressure values of four persons are
given below:
1. Mrs.X-90/60
2.Mr.X-160/120
3. Mr. Y-120/80
4.Mrs.Y-140/l00
Who among the following has normal blood pressure?
(a) Mrs. Y
(b) Mr. X
(c) Mrs. X
(d) Mr. Y
Ans : d

34. In the case of a ‘Test-tube baby’?
(a) fertilisation takes place inside the test tube.
(b) development of the baby takes place inside the test tube.
(c) fertilisation takes place outside the mother body.
(d) unfertilised egg develops inside the test tube.
Ans : c

35. Pituitary gland is present
(a) below the brain
(b) above the brain
(c) inside the brain
(d) nowhere near the brain
Ans : a

36. Which of the following organs is used in the purification of blood in human body?
(a) Liver
(b) Kidney
(c) Spleen
(d) Lungs
Ans : d

37. Cornea is a part of which of the following organs
of human body?
(a) Eye
(b) Ear
(c) Nose
(d)Heart
Ans : a

38. What is Funny Bone?
(a) A muscle
(b) A nerve
(c) A bone
(d) A blood vessel
Ans : b

39. Man cannot digest cellulose whereas cows can do so because?
(a) their gut contains bacteria capable of digesting cellulose.
(b) they have a many – chambered stomach.
(c) they have efficient grinding molars.
(d) they produce an enzyme cellulase which can digest cellulose.
Ans : a

40. Which of the following when taken by pregnant women, is found to be the cause of deformed children?
(a) Glycerol
(b) Xylidine
(c) Thalidomide
(d) None of these
Ans : c
41. The diploid number of chromosomes in human body is ?
(a) 24
(b) 40
(c) 46
(d) 48
Ans : c

42. The largest cell in the human body is
(a) Nerve cell
(b) Muscle cell
(c) Liver cell
(d) Kidney cell
Ans : a

43. Lichens are formed due to the symbiotic association of
(a) moss and fungi
(b) bacteria and fungi
(c) algae and fungi
(d) None of these
Ans : c

44. Insects form the largest class of animals living on land and sea. They are grouped into
(a) 22 orders
(b) 26 orders
(c) 29 orders
(d) 32 orders
Ans : c

45. Which of the following statements is true for planktons?
(a) They live on the surface of lake water.
(b They live on the bottom of lakes.
(c) They live on the plants growing in water.
(d) They live in the water column.
Ans : b

46. Which of the following has the smallest egg?
(a) Ostrich
(b) Humming bird
(c) Pigeon
(d) Homo sapiens
Ans : c

47. The population of which of the following is maximum on the earth?
(a) Reptiles
(b) Fishes
(c) Birds
(d) Beetles
Ans : d

48. Poison glands of snakes are homologous to
(a) stings of rays
(b) salivary glands of vertebrates
(c) electric organs of fishes
(d) sebaccous glands of mammals
Ans : b

49. The phylum chordata is characterised by the presence of
(a) spinal cord
(b) notochord
(c) nerve chord
(d) None of these
Ans : d

50. Which of the following activities is suppressed by the presence of auxins in plants?
(a) Growth of lateral buds
(b) Cell division
(c) Root initiation
(d) Development of fleshy fruits
Ans : c