Question

Secondary sexual characters in males develop under the influence of
(a) Estrogen
(b) Testosterone
(c) GH
(d) FSH

Answer 1

Hint: They are the only male sex hormone responsible for sexual and reproductive development. They are mainly produced within the testes with a very small amount produced within the adrenal glands. They are also produced in very small amounts in females.

Complete answer:
The testosterone production is controlled by the hypothalamus and pituitary gland. It’s responsible for the event of male sex organs during birth and the development of secondary sexual characteristics during puberty. It is mainly produced in the testes and belongs to a class of male hormones called androgens that are also known as steroids.
Male secondary sex characteristics include:
- Growth of body hair, as well as underarm, abdominal, chest hair, and pubic hair.
- Growth of facial hair.
- Expansion of larynx (Adam's apple) and deepening of the voice.
- Increased stature; adult males are taller than adult females, on average.
- Heavier skull and bone structure.
- Increased muscle mass and strength.
- Thickening of shoulders and chest; shoulders wider than hips.
- Increased secretions of oil and sweat glands.
Estrogen is the female sex hormone secreted from ovarian follicles and stimulate the event of female secondary sex organs.
Growth hormone (GH)  is additionally referred to as somatotropin hormone and stimulates body growth and carbohydrate, protein, and fat metabolism.
FSH (Follicle- stimulating hormone) is secreted from the anterior part of the pituitary. It stimulates the expansion of ovarian follicles in females and seminiferous tubules in males. This hormone also promotes spermatogenesis in males i.e. the method of formation of sperms from the germ cells.
So, the right answer is '(b) Testosterone'.
Note: During adolescence male testes and female ovaries mature. The matured gonads (sex organs) start to secrete hormones. These hormones are called sex hormones. The testosterone levels gradually decrease with age. It leads to impotence, low sperm count, shrunken testes, depression, irritability, etc.