The endocrine system is made up of glands that produce hormones which are released into the bloodstream to target specific organs and tissues. Hormones act as chemical messengers and control various bodily functions such as growth and development, metabolism, sexual function, and mood. The major glands of the endocrine system include the pituitary gland, thyroid gland, parathyroid glands, adrenal glands, pancreas, and gonads (ovaries and testes).