PERISTALSIS:-
Peristaltic movements are characteristics movements of the digestive tract by which food is moved along the cavity of the canal.
Definition:
It is a wave of contraction and relaxation of the circular and longitudinal muscles, which squeezes the food down along the digestive canal.
Occurrence:
Peristalsis starts just behind the food from the buccal cavity along the esophagus to the stomach and then along the whole alimentary canal.
Anti-peristalsis:
The reversal of peristalsis is called anti-peristalsis. As a result of an peristalsis the food may pass from the intestine back into the stomach and even into the mouth leading to vomiting.
Hunger Pang:
Hunger contractions are peristaltic contractions which are increased by low blood glucose level and are sufficiently strong to create an uncomfortable sensation called a “hunger pang”. Hunger pangs usually begin 12 to 24 hours after the previous meal or in less time for some people.
Effect of Gravity on the Movement of Material:
Gravity helps the movement of material through the esophagus especially when liquid are swallowed. However, the peristaltic contractions that move material through the esophagus are sufficiently forceful. Therefore a person can swallow even while doing a headstand
Noticeable
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