Question

Study the following flowchart. Name the hormones involved at each state. Explain their functions.

Hypothalamus→Pituitary→Testes→ Sperms

Answer 1

Hormonal sequence:

Hypothalamus — GnRH → Anterior pituitary — FSH and LH/ICSH → Testes — testosterone and inhibin → sperm production

1. GnRH: Released by the hypothalamus; stimulates the anterior pituitary to release FSH and LH/ICSH.
2. LH/ICSH: Acts on Leydig cells in the testes, stimulating testosterone secretion.
3. Testosterone: Supports spermatogenesis and the functioning of male reproductive organs.
4. FSH: Acts on Sertoli cells, which nourish and support developing germ cells and promote sperm development. Sertoli cells also secrete inhibin, which reduces FSH secretion by negative feedback.