The document defines key terms related to the endocrine system: the endocrine system communicates through chemical messengers called hormones secreted into the bloodstream by glands; the adrenal glands above the kidneys secrete hormones like epinephrine that arouse the body during stress; and the pituitary gland, most influential endocrine gland, regulates growth and controls other glands under the influence of the hypothalamus.

1. A few terms clarified

2. endocrine system—the body’s “slow” chemical communication system; a set of glands that secrete hormones into the bloodstream.

3. Hormones—chemical messengers, mostly those manufactured by the endocrine glands, that are produced in one tissue and affect another

4. Adrenal glands—a pair of endocrine glands, just above the kidneys. The adrenals secrete epinephrine and norepinephrine, which help to arouse the body in times of stress

5. Pituitary gland—the endocrine’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands

6. Pituitary gland—the endocrine’s most influential gland. Under the influence of the hypothalamus, the pituitary regulates growth and controls other endocrine glands

7. Glial cells—cells in the nervous system that support, protect, and nourish neurons