Explain how peristalsis and segmentation in the small intestine differ
What will be an ideal response?
As with other regions of the alimentary canal, peristalsis in the small intestine is accomplished by alternating contractions of the longitudinal and circular layers of smooth muscle in the muscularis externa. The primary function of peristalsis is to propel chyme toward the ileum and ultimately through the ileocecal valve to the cecum. However, segmentation, also known as intestinal churning, involves contractions of only the circular layer of smooth muscle, which produces a squeezing motion. The primary functions of segmentation are mechanical digestion and mixing the chyme with intestinal and pancreatic enzymes as well as bile.
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