peristalsis. involuntary wavelike muscular contrac

anatomy body bolus care carries circular cms contraction contractions cross cutaway diagram digestive disease distally distension downstream education epiglottis eristalsis esophagus gastric gastrointestinal gut health healthcare healthy histology human illustration inner intestine laboratory large longitudinal medical medicine movement muscle muscles oesophagus peristalsis peristaltic pharynx reflex relaxation response scheme science section several small sphincter stomach structure swallow tongue trachea tract vector villi wall wave wavelike