Medical Terminology

autonomic nervous system (ANS)

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The autonomic nervous system (ANS) controls several basic bodily functions, including heart rate, body temperature, breathing rate, digestion, skin sensation, bladder, sweat glands, and metabolism. The ANS regulates functions that are involuntary or that we usually cannot consciously influence. The ANS is made up of 3 parts: (1) sympathetic nervous system (responsible for the body’s “fight or flight” response, by increasing the heart rate and releasing energy); (2) parasympathetic nervous system (responsible for controlling body processes during relaxation and other ordinary situations, including slowing down heart rate and reducing blood pressure); and (3) enteric nervous system (responsible for governing the function of the gastrointestinal system through a mesh-like system of neurons [also called nerve cells]).