Question 132 Which of the following is true of testosterone? The production of testosterone is stimulated by FSH. Testosterone is produced by interstitial endocrine cells. Testosterone provides positive feedback on gonadotropin release. The release of testosterone surges during ejaculation. SOLUTION.PDF Question 133 Which male hormone provides negative feedback for the secretion of FSH? OGnRH O inhibin O ACTH O ICSH
The Correct Answer and Explanation is :
Question 132 Answer:
The correct statement is: Testosterone is produced by interstitial endocrine cells.
Explanation:
Testosterone is a steroid hormone primarily produced in the testes, specifically by interstitial endocrine cells (also known as Leydig cells). These cells are located between the seminiferous tubules in the testes and are responsible for the production of testosterone in response to signals from luteinizing hormone (LH), which is secreted by the anterior pituitary.
Here’s why the other statements are incorrect:
- The production of testosterone is stimulated by FSH: This is incorrect. Follicle-stimulating hormone (FSH) primarily stimulates the Sertoli cells in the testes, supporting sperm production, but does not directly stimulate testosterone production. LH, not FSH, stimulates the Leydig cells to produce testosterone.
- Testosterone provides positive feedback on gonadotropin release: This is false. Testosterone actually provides negative feedback to the hypothalamus and pituitary gland, inhibiting the release of gonadotropins (LH and FSH). This ensures the regulation of testosterone levels within a controlled range.
- The release of testosterone surges during ejaculation: This statement is incorrect. While testosterone levels can fluctuate throughout the day (with higher levels in the morning), they do not surge specifically during ejaculation. Ejaculation is a complex process, but it doesn’t cause a notable surge in testosterone.
Question 133 Answer:
The correct answer is: Inhibin.
Explanation:
Inhibin is a hormone secreted by the Sertoli cells in the testes. It plays a crucial role in regulating the levels of follicle-stimulating hormone (FSH). When sperm production is sufficient, inhibin is released to provide negative feedback on the anterior pituitary to reduce FSH secretion, thus preventing overproduction of sperm.
Here’s why the other options are incorrect:
- GnRH (Gonadotropin-Releasing Hormone): GnRH is produced by the hypothalamus and stimulates the release of LH and FSH from the anterior pituitary. It does not provide negative feedback on FSH.
- ACTH (Adrenocorticotropic Hormone): ACTH is a hormone secreted by the anterior pituitary that stimulates the adrenal glands to release cortisol. It does not directly affect FSH secretion.
- ICSH (Interstitial Cell-Stimulating Hormone): ICSH is another term for luteinizing hormone (LH) in males, which stimulates testosterone production by Leydig cells. It does not negatively regulate FSH secretion.
Thus, inhibin is the hormone that provides negative feedback to control FSH levels in males.