The autonomic nervous system consist of two divisions known as the sympathetic nervous system and the parasympathetic nervous system.
The sympathetic nervous system- functions like an emergency system. The impulses of this system take control of many of the internal organs when we do things such as exercise strenuously and when we are over come with very strong emotions like fear, anger, hat, anxiety. This system helps the body cope with stress. It causes things to change so the body is able to adapt to the stress such as the heartbeat increases, blood vessels constric, glands secrete more, and salivary and digestive glands secrete less.