The mechanical systems of the gut must move nutrients in whatever complex
ways may be necessary in each situation for digestive and absorptive processes to be
complete. The mechanical processes vary from one species to another but they differ
mainly in quantitative rather than qualitative terms. This chapter deals with the
movements of the gastrointestinal musculature throughout the tract. Most of these
patterns of motion are inferred rather that observed directly, for the available methods
rarely permit the direct and detailed observation of the muscular behavior in vivo.
Keywords: Contractility, esophagus, flow, large intestine, motility pattern,
peristalsis, relaxation, small intestine, stomach.
