Ans. Sympathetic nervous system prepares body to deal with emergency situations. This Is often called the "fight or flight" response. During an emergency situation, this system takes necessary actions. For example; it dilates pupils, accelerates heartbeat, increases breathing rate and inhibits digestion. When stress ends, the parasympathetic nervous system takes action and normalizes all the functions*. It causes pupils to contract, promotes digestion, and slows the rate of heartbeat and breathing rate.