In physiology it is a chemical substance that is secreted by a specialized cell, usually found in an endocrine gland. It is also known as the body's chemical messenger. They travel through the bloodstream to the body's tissues and organs.
An organic chemical produced by a body to regulate or modify the activity of its tissues. There are specific hormones for each case. The word is inspired by the Greek 959; 961; 956; 969; 957; ( ormoon "excited" ) for the function they fulfill .