Answer:Smooth muscle is called involuntary muscle because you can not control this type of muscle movement. These muscles line internal organs, blood vessels, and organs such found in the digestive and reproductive systems.
Peristalsis is a series of wave-like muscle contractions that move food through the digestive tract. It starts in the esophagus where strong wave-like motions of the smooth muscle move balls of swallowed food to the stomach.
