Question

Hormone responsible for the development of mustache and beard in man
(a) Sex corticoid
(b) Testosterone
(c) Thyroxine
(d) Thymosin

Answer 1

Hint: Chief androgen which is secreted by the Leydig cells of testis and zona reticularis of the adrenal gland which helps in spermatogenesis and development of secondary sexual characters in males.

Complete step by step answer:
The adrenal cortex in the adrenal gland is differentiated into 3 zones namely zona glomerulosa, zona fasciculata, zona reticularis. The last zone i.e, zona reticularis synthesizes sex hormones. Androgens are the male sex hormones and the chief androgen is testosterone. This hormone is also secreted by the Leydig cells present in the testis. Testosterone helps in the development of male secondary sexual characters such as the development of facial hair, pubic hair, axial hair, aggressiveness, and low pitch voice during puberty.
So, the correct answer is ‘Testosterone’.

Additional information:
- Testis in males is considered as male gonadal glands. They are paired located in a sac called scrotum outside the abdomen.
- Testis is considered as a cytogenetic organ. A cytotoxic organ is an organ which produces cells
- Testis can produce both sperms and male sex hormones.
- The Leydig cells or interstitial cells of Leydig which lie in inter seminiferous tubule spaces of testis produce androgens. Testosterone is considered to be a chief androgen.
- A pair of adrenal glands are also present on the anterior part of the kidney which is differentiated into 3 zones: zona glomerulosa, zona fasciculata, zona reticularis.
- Zona glomerulosa synthesizes mineralo- corticoids, zona fasciculata secretes glucocorticoids and zona reticularis secretes sex hormones such as testosterone.
- Testosterone secreted by testis and zona reticularis helps in sperm production, development of secondary sexual characters in males such as the growth of axial, pubic, and facial hair, muscular growth, aggressiveness, masculine voice, etc.

Note: Testosterone helps in the development, maturation, and functioning of accessory sex organs in males such as epididymis, vas deferens, seminal vesicles, prostate gland, and urethra, etc.
Luteinizing hormone in males helps in the stimulation of Leydig cells.