What do parasympathetic nerves stimulate?

The parasympathetic nervous system is primarily responsible for promoting the "rest and digest" functions of the body. This part of the autonomic nervous system works to conserve energy and enhance functions that occur during restful states. When parasympathetic nerves are stimulated, they activate digestive activity, promoting processes such as salivation, gastric secretion, and increased peristalsis in the intestines. This stimulation is crucial for efficient digestion and nutrient absorption after eating.

In contrast, the other functions—muscle contraction, respiratory rate, and cardiac output—are primarily influenced by the sympathetic nervous system, which prepares the body for "fight or flight" responses. Thus, while muscle contractions can occur due to various stimuli, they are not specifically a function of parasympathetic stimulation. Similarly, respiratory rate and cardiac output are typically elevated during stress or physical activity, which again relies more on sympathetic activation rather than parasympathetic influence.