2.28 explain how and why food is moved through the gut by peristalsis

Peristalsis: A series of coordinated, rhythmic muscle, that occurs automatically to move food through the digestive track.

How:

·         Two muscles in esophagus circular (inner) and longitudinal (outer)

·         Muscles work antagonistically

·         When circular contracts the canal gets narrower

·         When longitudinal contracts the canal gets shorter

·         Moves food down in inchworm type motion