Describe the structure and function of the esophageal sphincters. What occurs if the lower sphincter fails?
What will be an ideal response?
Answer: A ring of smooth muscle around the esophagus forms each sphincter. Contraction of the muscles closes the sphincter; relaxation opens it. Opening and closing of these sphincters is tightly controlled by the nervous system, and integrated with the swallowing and vomiting reflexes. Failure of the lower esophageal sphincter results in heartburn, as acid from the stomach is pushed up into the esophagus.
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A) reflex arc. B) ramus. C) ganglion. D) tract. E) circuit.
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Answer the following statement true (T) or false (F)
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