Anatomy and Physiology II Practice Test

The secretion of the male sex hormone testosterone is primarily carried out by interstitial cells, also known as Leydig cells, which are located in the testes. These cells play a crucial role in male reproductive physiology by producing testosterone in response to stimulation by luteinizing hormone (LH) from the pituitary gland. Testosterone is essential for the development of male secondary sexual characteristics, such as increased muscle mass, deepening of the voice, and growth of facial and body hair.

Follicular cells are associated with the ovarian follicles and primarily produce estrogen and progesterone, while parafollicular cells, located in the thyroid gland, secrete calcitonin, which helps regulate calcium levels in the blood. Epidermal cells are part of the skin's outer layer and do not have a role in hormone production. Thus, the interstitial cells are correctly identified as the primary producers of testosterone in males.