Explain the Actions of Autonomic Nervous System (ANS)

The actions of the autonomic nervous system are largely involuntary (in contrast to those of the somatosensory system). The autonomic nervous system consists of sensory neurons and motor neurons that run between the central nervous system (especially the hypothalamus and medulla oblongata) and various internal organs such as the heart, lung, viscera and glands.

It is responsible for monitoring conditions in the internal environment and bringing about appropriate changes in them. The contraction of both smooth muscle and cardiac muscle is controlled by motor neurons of the autonomic system. We must also emphasize here that the autonomic nervous system also differs from the somatosensory system in using two groups of motor neurons - the preganglionic and postganglionic - to stimulate the effectors instead of one.