All of the systems that are aroused by the sympathetic nervous system are relaxed by the parasympathetic nervous system.
autonomic nervous system (ANS) is a part of the central nervous system that controls all parts that the human cannot have a control on (which are done automatically) like heart rate and breath
ANS is divided in two opposite systems: sympathetic and parasympathetic:
Parasympathetic nervous system: caracterized by the tag "rest and digest" it decreases the heart rate, blood pressure, and breath. It increases the gastrointestinal motricity, letting the organism resting (this happen after a meal).
Sympathetic nervous system: caracterized by the tag "fight or flight" it increases the heart rate, blood pressure, and breath. It decreases the gastrointestinal motricity, letting the organism focus on its environment (this happen when we are in danger).
