Chemical Coordination and Integration — Page 6 | NEET Biology

Q51

A candidate vaccine for male contraception is based on

A follicle stimulating hormone

B progesterone

C testosterone

D luteinizing hormone

Correct Answer

Option C

Solution

(c) LH activates Leydig's cells to secrete testosterone. FSH stimulates spermatogenesis.

Q52

Oxytocin is involved in

A lactation

B childbirth

C ovulation

D implantation of the embryo

Correct Answer

Option B

Solution

(b) Oxytocin stimulates strong uterine contractions during parturition.

Q53

Progesterone prevents pregnancy by

A preventing the cleavage of the fertilized egg

B preventing the formation of ova

C blocking ovulation

D creating unfavourable environment for sperms

Correct Answer

Option C

Solution

(c) Progesterone suppresses ovulation and production of LH.

Q54

Melanocyte stimulating hormone (MSH) is produced by

A parathyroid

B pars intermedia of pituitary

C anterior pituitary

D posterior pituitary

Correct Answer

Option B

Solution

(b) MSH is secreted by the intermediate lobe (pars intermedia) of the pituitary gland.

Q55

Melatonin is produced by

A thymus

B skin

C pituitary

D pineal gland

Correct Answer

Option D

Solution

(d) Melatonin is secreted by pineal gland. It regulates the biological clock in mammals.

Q56

Which of the following radioactive isotope is used in the detection of thyroid cancer?

A Iodine-131

B Carbon-14

C Uranium-238

D Phosphorus-32

Correct Answer

Option A

Solution

(a) Radioactive Iodine-131 is used for detection of thyroid cancer because thyroid gland uses iodine.

Q57

Acromegaly is caused by

A excess of G.H.

B excess of thyroxin

C deficiency of thyroxin

D excess of adrenalin

Correct Answer

Option A

Solution

(a) Acromegaly is caused by over secretion of somatotrophic hormone (Growth hormone) after adolescence.

Q58

Adrenaline directly affects on

A S.A. node

B b-cells of Langerhans

C dorsal root of spinal cord

D epithelial cells of stomach

Correct Answer

Option A

Solution

(a) Adrenaline directly acts on the S.A. node, increasing heart rate.

Q59

When both ovaries are removed from rat then which hormone is decreased in blood?

A Oxytocin

B Prolactin

C Estrogen

D Gonadotropin releasing factor

Correct Answer

Option C

Solution

(c) Estrogen is released from the ovarian follicles, so removal of ovaries decreases estrogen.

Q60

Which of the following is an amino acid derived hormone?

A Epinephrine

B Ecdysone

C Estriol

D Estradiol

Correct Answer

Option A

Solution

(a) Epinephrine is derived from tyrosine (amino acid) by removal of carboxyl group. It is a catecholamine.