The endocrine system is composed of glands and functions as a communication system in order to elicit a response from the body and regulate and maintain homeostasis. Endocrine glands produce hormones, which are released into the bloodstream and distributed to body cells. Hormones can then act as chemical messengers to target specific cells to produce a response. Hormones can further be classified as steroid hormones and amino acid hormones, as described below.
