ABSTRACT
Hormones are produced in many places in the body, including specialized endocrine glands. Hormones are usually released into the blood and circulate to target cells, where they act by attaching to specific receptors, in the same way as neurotransmitters, producing a change in the activity of the target cells. The pituitary gland releases many hormones that act on other endocrine glands, controlling their hormone release. The anterior pituitary gland has a circulatory link with the hypothalamus and produces a variety of hormones, most of which control other glands. Surrounding the adrenal medulla is the adrenal cortex, which produces a large number of different steroid hormones, falling into three classes. In men most testosterone derives from the testes, but in women most circulating androgens are secreted by the adrenal cortex. The pancreas has a variety of functions, all related to the digestion, absorption, and use of food and its products..
