Peristalsis is a radially symmetrical contraction and relaxation of muscles which propagates in a wave down the muscular tube, in an anterograde fashion. In humans, peristalsis is found in the contraction of smooth muscles to propel contents through the digestive tract. It is wave contraction of longitudinal and circular muscles preceded by wave relaxation of these muscles. Earthworms use a similar mechanism to drive their locomotion.
American scientists conducted a study that showed that gastroesophageal reflux disease, one of the manifestations of which is heartburn, is associated with a high risk of developing cancer of the larynx and...