What do gonads refer to in the endocrine system?

Gonads specifically refer to the sex glands in the endocrine system, which are responsible for producing gametes (sperm in males and eggs in females) and secreting sex hormones such as testosterone and estrogen. These hormones play crucial roles in the development of secondary sexual characteristics, reproductive functions, and overall sexual health. The gonads include the testes in males and the ovaries in females, and their functions are fundamental in regulating various aspects of sexual reproduction and hormonal balance.

The other options focus on different glands in the endocrine system that serve various purposes. For instance, adrenal glands are involved in producing hormones related to stress response and metabolism; pituitary glands, often referred to as the "master gland," regulate many bodily functions through hormone release; and thyroid glands are primarily responsible for regulating metabolism through thyroid hormones. However, none of these glands specifically produce gametes or are directly linked to sexual reproduction in the way that gonads are.