Assertion: esophagus's sphincter | /r/HasProperty | the structure
Facets:
Source sentences:
text: Furthermore, the upper esophageal sphincter is the structure responsible for closing the upper esophageal opening.
text: The upper esophageal sphincter is the structure, which closes the upper esophageal opening.
text: The lower esophageal sphincter is the structure the keeps acid and stomach contents from spurting up the esophagus as the stomach undergoes muscular contractions.