Question

Identify the correct statement on ‘inhibin’
(A) Is produced by granulosa cells in the ovary and inhibits the secretion of FSH
(B) Is produced by granulosa cells in the ovary and inhibits the secretion of LH
(C) Is produced by nurse cells in testes and inhibits the secretion of LH
(D) Inhibits the secretion of LH, FSH, and Prolactin

Answer 1

Hint: Inhibin is a peptide-protein which is secreted in both the male and female body. Its important function is to induce a negative feedback mechanism and inhibit the secretion of certain hormones. It is produced by granulosa cells in the ovary and sertoli cells in the male reproductive system, which inhibits the secretion of follicle-stimulating hormone (FSH) by the anterior pituitary.

Complete answer: Inhibin is a polypeptide protein which is secreted by sertoli cells in males and granulosa cells in females. Its function is to induce negative feedback mechanism and inhibit the secretion of Follicle-stimulating hormone by the anterior pituitary gland. The major function of follicle-stimulating hormone is to stimulate the formation and function of granulosa cells. Thus, the relationship between inhibin and follicle-stimulating hormone (FSH) is a typical negative feedback mechanism. Inhibin is also produced in small amounts by the sertoli cells in male reproductive system.

Understanding the options one by one,
Option (A) Is produced by granulosa cells in the ovary and inhibits the secretion of FSH: Inhibin is produced by granulosa cells in the ovary and induces a negative feedback mechanism on FSH. Therefore, this is the correct answer.
Option (B) Is produced by granulosa cells in the ovary and inhibits the secretion of LH: Progesterone and estrogen inhibit the secretion of Luteinizing hormone and therefore, this is not the correct answer.
Option (C) Is produced by nurse cells in testes and inhibits the secretion of LH: Inhibin in males is produced by the sertoli cells and not nurse cells and it doesn’t inhibit the secretion of LH. Therefore, this is not the correct answer.
Option (D): Inhibits the secretion of LH, FSH, and Prolactin: Inhibin doesn’t inhibit the secretion of LH and prolactin and hence, this is not the correct answer.

Note: It is important to know the significance of each hormone and the cells which secrete them. The follicle-stimulating hormone secreted by the anterior pituitary acts on the ovary and helps in the formation of granulosa cells. When enough granulosa cells are produced, it starts producing inhibin which inhibits the secretion of FSH.