Illustration of the Endocrine System
Illustration of the Endocrine System
The Basics

The endocrine system is made up of glands that produce hormones that circulate throughout the bloodstream. Glands are groups of cells that make and give off chemicals. They do this by selecting and removing materials from blood. Then they process and secrete the chemicals in the form of hormones throughout the body, but some glands secrete to specific parts of the body. The endocrine system is the main hormone producer and it regulates metabolism, growth, and sexual development/function. (Downshen, 2008)

The Anatomy

The main glands are the hypothalamus, pituitary, thyroid, parathyroids, adrenals, pineal body, pancreas and the reproductive glands (in the form of ovaries and testes).
The hypothalamus is for regulation of metabolism, temperature, and the condition of being full as in eating. Also, it secrest hormones that "stimulate or suppress the release of hormones in the pituary gland".
The pituary gland functions mainly to produce growth hormones and also produces hormones to control other endocrine glands.
The thyroid gland regulates metabolism as well as helps in bone growth and development of brain and nervous system in children. These hormones help to maintain heart rate, digestion, muscle tone, blood pressure, and reproduction.
The parathyroid glands regulate calcium levels in the blood and bones.
The adrenal glands regulate metabolism, as well as balance salt and water levels in the body. They also have hormones to ease physical or emotion stress.
The pineal glands regulate and produce melatonin which regulates the body's sleep cycle. The more melatonin you have, the more sleepy you get.
The reproductive glands produce sex hormones. In males, the testes produce testosterone and sperm production. The ovaries produce estrogen and progesterone and eggs, as well as menstruation cycles. Both control male/female development, like breast, etc.
The pancreas secretes hormones. These hormones are known as insulin and glucagon that regulate the level of sugar or glucose in the blood. (Rieser, 2008)


Dowshen, S. (2007, July). Endocrine System. Retrieved November 7, 2008, from
Rieser, M. (2005, December 30). Anatomy of the Endocrine System. Retrieved November 7, 2008, from