Describe factors within the stomach and duodenum, and those outside the digestive system that affect gastric motility and emptying
What will be an ideal response?
(1) Within the stomach: Filling the stomach with chyme causes stretch, which has a direct effect on gastric smooth muscle excitability, as well as acting through the intrinsic plexuses, the vagus nerve, and gastrin. The result is increased motility and emptying. In addition, having more fluid in the stomach causes more rapid emptying.
(2) In the duodenum: The presence of fat, acid, hypertonicity, or distension initiates the enterogastric reflex or triggers the release of enterogastrones (secretin, cholecystokinin). These factors in the duodenum inhibit further gastric motility and emptying until the duodenum has coped with factors already present.
(3) Outside the digestive system: Emotion can alter autonomic balance, which can either stimulate or inhibit motility and emptying. Intense pain increases sympathetic activity and inhibits motility and emptying.
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What will be an ideal response?
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Answer the following statement true (T) or false (F)
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