Solution:

• Peristalsis is a series of wave-like muscle contractions that moves food to different processing stations in the digestive tract.
• The process of peristalsis begins in the esophagus when a bolus of food is swallowed.
• Peristalsis is a radially symmetrical contraction and relaxation of muscles that propagates in a wave down a tube, in an anterograde direction.
• Peristalsis is progression of coordinated contraction of involuntary circular muscles, which is preceded by a simultaneous contraction of the longitudinal muscle and relaxation of the circular muscle in the lining of the gut.
• Earthworms use a similar mechanism to drive their locomotion.