1. The peripheral nervous system that controls involuntary functions of the body is known as Autonomous nervous system.
2. It has voluntary control of muscles of some areas of skin and the skeletal muscle.
3. For example when we enter a dark room we can not see anything immediately. Slowly we are able to see the things around us in the room.
4. This is because of increase in diameter of pupil, which allows more light in.
5. When we come out of the dark room into broad day light the diameter of the pupil decreases allowing less light to enter into the eyes.
6. Both these functions occur under the influence of the autonomous nervous system.
