The presence of muscular tissue in the alimentary canal indicates that some sort of movements must be present in the gastro-intestinal tract. As a matter of fact, the alimentary canal does move, its different parts showing different kinds of movements. Reason for Movement: If one recollects the chief functions of the digestive tract, such as digestion, secretion, absorption, defecation etc., [...]
In this article we will discuss about the four main types of movements that are seen in stomach. Type # 1. Movements of the Fundus and Body: A peristaltic wave follows the basic electrical rhythm (B.E.R.) of stomach. It starts in the longitudinal musÂcle of greater curvature as a pacemaker and passes over the body, antrum and pylorus at a [...]
Deglutition or swallowing is probably a reflex phenomenon. Higher centres facilitate this reflex. Once aroused, the swallowing centre in the medulla evokes the complete act of swallowing by discharge through six nuclei and the motor neurones. This reflex act occurs in three stages: (1) First or oral, (2) Second or pharyngeal, and (3) Third or oesophageal (Fig. 9.46). (1) First [...]