Question

Spermatogenesis starts at the age of puberty due to a significant increase in secretion of Gonadotropin Releasing Hormone (GnRH). Increased levels of GnRH stimulate the secretion of two gonadotropins which are:

• A. Luteinising Hormone and Androgens
• B. Follicle Stimulating Hormone and Androgens
• C. Luteinising Hormone and Follicle Stimulating Hormone
• D. Luteinising Hormone and Testosterone

Hint:

Remember the sequence: GnRH \(\rightarrow\) Anterior Pituitary \(\rightarrow\) LH + FSH \(\rightarrow\) Testosterone production and spermatogenesis.

Answer 1

The Correct Option is C

Concept: The male reproductive system is regulated by the Hypothalamic–Pituitary–Gonadal (HPG) axis. Hormonal interactions between hypothalamus, pituitary gland, and testes control spermatogenesis.

Step 1: Understanding the role of hypothalamus at puberty.
At puberty, hypothalamus becomes more active and begins secreting Gonadotropin Releasing Hormone (GnRH) in larger amounts.

Step 2: Identifying the target organ of GnRH.
GnRH travels to the anterior pituitary gland through blood circulation and stimulates pituitary cells.

Step 3: Determining the hormones released by anterior pituitary.
In response to GnRH stimulation, anterior pituitary secretes two gonadotropins:

• Luteinising Hormone (LH)
• Follicle Stimulating Hormone (FSH)

Step 4: Understanding the functions of LH and FSH.
LH acts on Leydig cells present in testes and stimulates secretion of testosterone and other androgens.
FSH acts on Sertoli cells and supports the process of spermatogenesis.

Step 5: Eliminating incorrect options carefully.
- Androgens and testosterone are steroid hormones, not gonadotropins.
- Only LH and FSH are classified as gonadotropins secreted by anterior pituitary. Thus, the correct answer is Luteinising Hormone and Follicle Stimulating Hormone.