Biology (Part-II) (UPSC)

11. Consider the following statements. [1996]

AIDS-is transmitted

1. By sexual intercourse

2. By blood transfusion

3. By mosquitoes and other blood sucking insects

4. Across the placenta

(a) 1, 2 and 3 are correct
(b) 1, 2 and 4 are correct
(c) 1, 3 and 4 are correct
(d) 1 and 3 are correct

Correct Answer: (b) 1, 2 and 4 are correct

Solution:AIDS is a viral disease. The virus is called HIV. This disease transmitted by sexual intercourse, blood transfusion and from pregnant mother to baby through placenta.

12. Which of the following would lead to malnutrition? [1996]

1. Overnutrition

2. Undernutrition

3. Imbalanced nutrition

Select the correct answer by using the codes given below Codes:

(a) 2 alone
(b) 2 and 3
(c) 1 and 3
(d) 1, 2 and 3

Correct Answer: (d) 1, 2 and 3

Solution:Malnutrition is defined as the insufficient, excessive or imbalanced consumption of nutrients. So under nutrition, over nutrition and imbalanced nutrition leads to malnutrition.

13. People drinking water from a shallow hand pump, are likely to suffer from all of the following diseases except : [1996]

(a) Cholera
(b) Typhoid
(c) Jaundice
(d) Fluorosis

Correct Answer: (d) Fluorosis

Solution:Cholera, Typhoid and Jaundice are water borne diseases. In shallow hand pumps there is possibility of microbial contamination (bacteria) to water. But fluorosis occurs due to excess amount of fluorine found in water.

14. Besides proteins and carbohydrates, other elements of nutritional value found in milk, include : [1996]

(a) calcium, potassium and iron
(b) calcium and potassium
(c) potassium and iron
(d) calcium and iron

Correct Answer: (b) calcium and potassium

Solution:Besides proteins and carbohydrates, approximately 67% of calcium, 35% of magnesium and 44% of the phosphorus found in milk.

15. Fat present below the skin surface in our body, acts as a barrier against: [1996]

(a) Loss of heat from the body
(b) Loss of essential body fluids
(c) Loss of salts from the body
(d) Entry of harmful micro-organisms from the environment

Correct Answer: (a) Loss of heat from the body

Solution:Fat present below the skin surface in our body, act as a insulator against loss of heat from the body. The deposited fat works as barrier, which prevents loss of heat.

16. The major chemical compound found in kidney stones is: [1996]

(a) urea
(b) calcium carbonate
(c) calcium oxalate
(d) calcium sulphate

Correct Answer: (a) urea

Solution:The composition of kidney stone is :
Calcium oxalate : 80%, Uric acid : 5%, Amino acid cystine : 2%, Magnesium and 13% ammonium phosphate.

17. The pituitary gland by virtue of its tropic hormones controls the secretaoy activity of other endocrine glands. Which one of the following endocrine gland can function independent of the pituitary gland? [1997]

(a) Thyroid
(b) Gonads
(c) Adrenals
(d) Parathyroid

Correct Answer: (d) Parathyroid

Solution:Parathyroid gland is not controlled by pituitary. The parathormone which is secreted from this gland regulates calcium and phosphorus ion in body.

18. Oxygen transportation in a human body takes place through : [1997]

1. Blood

2. Lungs

3. Tissue

The correct sequence of transportation is

(a) 1, 2, 3
(b) 3, 1, 2
(c) 2, 1, 3
(d) 1, 3, 2

Correct Answer: (c) 2, 1, 3

Solution:In human body oxygen first comes through lungs. From lungs to different tissue via blood.

19. Corpus luteum is a mass of cells found in : [1997]

(a) Brain
(b) Ovary
(c) Pancreas
(d) Spleen

Correct Answer: (b) Ovary

Solution:Corpus luteum is a mass of cells found in ovary. It produces progesterone hormone. If the ovary is not fertilised, the corpus-luteum degenerates after about two weeks and is gradually replaced by ordinary ovary tissue.

20. Alpha-keratin is a protein, present in: [1997]

(a) Blood
(b) Skin
(c) Lymph
(d) Eggs

Correct Answer: (b) Skin

Solution:Alpha keratin is a protein, found in skin, hair, nail, claws and hooves of animals.

Alpha Keratin is a coiled-coil. It is strong. inextensible, insoluble and chemically inert. Alpha Keratin is found in hair, wool, horn, and tails.