Question

Testosterone is released by the testes in response to luteinizing hormone, released from the pituitary gland. As circulating testosterone levels rise, they act on the pituitary gland to reduce the secretion of luteinizing hormone, thus reducing the production of testosterone. This is an example of

a. positive feedback.
b. negative feedback.
c. adaptation.
d. acclimation.

Answer 1

Testosterone production is regulated by a negative feedback loop involving the hypothalamus, pituitary gland, and Leydig cells.

Step-by-step explanation:

The regulation of testosterone production involves a negative feedback loop. When testosterone levels rise, it acts on the pituitary gland to reduce the secretion of luteinizing hormone (LH), which in turn reduces the production of testosterone. This process helps to maintain testosterone levels within a narrow range.

Here is the step-by-step explanation:

1. Low blood concentrations of testosterone stimulate the hypothalamus to release gonadotropin-releasing hormone (GnRH).
2. GnRH stimulates the anterior pituitary gland to release LH into the bloodstream.
3. LH binds to Leydig cells in the testes and stimulates the release of testosterone.
4. When testosterone levels reach a critical threshold, testosterone itself binds to receptors on the hypothalamus and the anterior pituitary, inhibiting the synthesis and secretion of GnRH and LH, respectively.
5. This negative feedback loop reduces the production of testosterone when its levels are high, and stimulates its production when its levels are low.