Final answer:
The sympathetic and parasympathetic parts of the autonomic nervous system have opposing effects on the visceral organs, where the sympathetic division stimulates "fight or flight" responses and the parasympathetic division supports "rest and digest" functions.
Step-by-step explanation:
The autonomic nervous system is divided into the sympathetic and parasympathetic divisions, each having different effects on the viscera. Sympathetic stimulation generally prepares the body for "fight or flight" responses, which includes actions like pupil dilation (mydriasis), inhibition of salivation, increased heart rate, bronchodilation, decreased digestion, and inhibition of the contraction of the bladder.
On the other hand, parasympathetic stimulation often promotes "rest and digest" states, leading to pupil constriction (miosis), stimulation of salivation, decreased heart rate, bronchoconstriction, and increased digestion. The two systems often act in opposition to maintain homeostasis within the body.