Behavior is defined as the way one acts or behaves, especially towards others. Behavior is controlled by a system in the body called the endocrine system. The endocrine system is made up of glands whose secretions pass directly into the bloodstream or lymphatic system. This system is responsible for growth, mood, tissue function, metabolism, sexual function, and reproductive processes. The endocrine system affects almost every organ and cell in the body. Hormones and glands make up this system. As with any system, diseases dangerous to the body can occur. Hormones are an important part of the endocrine system. They are released from the endocrine tissue into the bloodstream. As the hormones travel through the bloodstream, they target a tissue where they will initiate a response. Endocrine glands, which are a special group of cells, produce hormones. Endocrine glands usually have no ducts and are vascularized. The kidney, heart and liver support the secondary endocrine systems. A small change in hormones can cause big changes in the body and cells. If there are too many or a...