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.
When to train to increase life longevity
Few will argue about the importance of exercise to increase life longevity. But about the best time of day for them, opinions differ. Coach Deanna Hammond-Blackburn believes that it is best to...
Heartburn can be a manifestation of a fatal illness
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...