Question

The ______ controls the amount of food that moves back up the esophagus.

a) Gastric mucosa.
b) Pyloric sphincter.
c) Duodenum.
d) Cardiac sphincter.

Answer 1

The cardiac sphincter, or gastroesophageal sphincter, controls the amount of food moving back up the esophagus by opening to allow food into the stomach and contracting to prevent reflux.

Step-by-step explanation:

The control of food movement back up the esophagus is managed by a ring-like muscle known as a sphincter. Specifically, the cardiac sphincter, also referred to as the gastroesophageal or lower esophageal sphincter, is responsible for this function. When food is swallowed, this sphincter relaxes to allow the bolus to pass into the stomach and then contracts to prevent the acidic contents of the stomach from refluxing back into the esophagus. This prevents conditions like heartburn or gastroesophageal reflux disease (GERD). Therefore, the correct answer to the question is d) Cardiac sphincter.