Explain the Propulsive Movement

The basic propulsive movement of the gastrointestinal tract is peristalsis. Peristalsis is the movement by which the gastrointestinal canal, having both longitudinal and circular muscle Jibres, help propel the contents. The usual stimulus for peristalsis is distention i.e. if a large amount of food collects at any point in the gut, the distention stimulates the gut wall 2 to 3 cm above this point. A contractile ring appears and a peristaltic movement starts. Strong peristaltic waves occur about once every 20 seconds in the stomach. They become intense approximately at the incisura angularis, from which they spread through the antrum. The movement is necessary to propel the food mass onwards and to bring it in contace with the gastric juice.

Peristaltic movements take place in the large intestine also. It is called mass movement. Mass movement propels the faecal contents towards the anus.