Image by Robina Weermeijer

Organ Systems

Endocrine System

The endocrine system is composed of organs called glands that produce chemical messengers called hormones.  Hormones are released by glands directly into the bloodstream and latch onto certain receptors throughout the body to produce a response and control processes such as metabolism, sleep, blood pressure, emotions, growth/development, and sexual function and fertility. There are many different types of glands within the endocrine system, including the pituitary gland, thyroid gland, parathyroid glands, adrenal glands, pancreas, testes, ovaries, pineal gland, thymus, and hypothalamus.  These glands are divided into exocrine glands and endocrine glands.  Exocrine glands produce substances that are carried to the surface of the body and released while endocrine glands secrete hormones directly into the bloodstream.

Diagram of the Endocrine System




Cleveland Clinic. (2020, May 12). Endocrine system.

Johns Hopkins Medicine. (n.d.). Anatomy of the endocrine system.

National Cancer Institute. (n.d.). Introduction to the endocrine system.