The coordinated, rhythmic, serial contraction of smooth muscle that forces food through the digestive tract is called peristalsis. It is a series of contractions of the muscles that is wave like which moves the food into the different parts of the digestive system. It begins in the esophagus when a food is being swallowed. These are involuntary motion of the circular and longitudinal muscles. It happens in the esophagus, the stomach and the intestines. It is the central nervous system that initiates and controls this process. This motion is not only limited to the digestive tract but can also be found on other systems in the body.
