How do sympathetic and parasympathetic nervous systems work to..?

Well the sympathetic and parasympathetic systems balance each other out. They are the subsystems of the Autonomic nervous system, which control the internal organs but they rely on the somatic nervous system, which controls skeletal movements.Sympathetic system is the "fight or flight" system. Epinephrine is the main hormone involved with the whole process of it. It increases heart rate, doesn't let you salivate, dialate pupils, digestive system shuts down, and bronchi are dialated as well. Then, parasympathetic system, "feed or breed" system, kicks in when you're calming down. Unlike the sympathetic system, it doesn't happpen all at once, or else you'd faint. Parasympathetic system stimulates digestive system and slows down the heart rate.
(To attain sexual arousal, you need parasympathetic and to reach sexual climax, you need the sympathetic system.)

hi...........
          well....sympathetic nervous system (sns) and parasympathetic n s r type of perinial nervous system..sns readies the body to fight against odd circumstances....and pns helps the body regain normality after odd circumstances..
                bye....

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