What Is the Esophagus?

6. Swallowing

After a person chews their food, the mouth passes it through the pharynx into the esophagus. Here, peristaltic contractions of striated muscle propel the food downward. The upper esophageal sphincter then relaxes to allow the food through. In the center of it, a combination of striated and smooth muscles work together to push the food to the lower esophageal sphincter. The sphincter relaxes, allowing the food to enter the stomach. The muscle contractions occur as a reflex when the body senses food in the mouth, and to any sensation of food in the esophagus itself.

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