Human Body

Nerves and Senses

How is the autonomic nervous system organized?

The autonomic nervous system regulates “involuntary” activity, which is not controlled on a conscious level. It consists of two divisions: the sympathetic nervous system and the parasympathetic nervous system. The sympathetic division is often called the “fight or flight” system because it usually stimulates tissue metabolism, increases alertness, and generally prepares the body to deal with emergencies. The parasympathetic division is considered the “rest and repose” division because it conserves energy and promotes sedentary activities, such as digestion.


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