Hormones are chemical messengers that are produced by glands in the endocrine system, which is a network of glands and organs located throughout the body. These glands include the pituitary gland, thyroid gland, adrenal gland, and gonads (ovaries and testes). Hormones are released into the bloodstream and travel to various organs and tissues, where they help regulate various bodily processes, such as growth, metabolism, and reproduction.