What is Peristalsis?
Peristalsis is a series of muscle contractions and relaxations which occur along the course of the intestinal tract to push food and waste products through. In some cases, people can actually feel peristalsis as it occurs, especially in the case of movements of the large intestine. The basic principles behind natural peristalsis in the body have also been adapted for peristaltic pumps, devices which utilize the same techniques used by the body to push fluids from place to place. The way in which peristalsis works is fairly simple. When food or water enters the gastrointestinal tract, the muscles start to compress and relax in a wave-like motion to push the material through. In the case of someone swallowing a bite of apple, when the apple reaches the esophagus, bands of smooth muscle alternate squeezing and relaxing movements. As the muscle squeezes, the apple moves to the area where the muscle is relaxed, which will be further down the esophagus. The muscles further up stay contracted
