Question

Describe the lower esophageal sphincter and indicate its function

A) A. The lower esophageal sphincter prevents the backflow of stomach contents into the esophagus, maintaining a one-way passage.
B) A. The lower esophageal sphincter regulates the entry of food from the stomach into the small intestine.
C) A. The lower esophageal sphincter controls the release of bile into the duodenum for digestion.
D) A. The lower esophageal sphincter facilitates the absorption of nutrients in the small intestine.

Answer 1

The lower esophageal sphincter functions as a valve that allows food to pass from the esophagus into the stomach and prevents the backflow of stomach contents, protecting against heartburn and GERD.

Step-by-step explanation:

The lower esophageal sphincter, also referred to as the gastroesophageal or cardiac sphincter, is a crucial anatomical structure located at the junction of the esophagus and stomach. Its primary function is to act as a valve regulating the movement of food from the esophagus into the stomach. This sphincter operates by relaxing to allow the passage of a food bolus into the stomach and then contracting to prevent the backflow of stomach acids and contents into the esophagus, which can cause heartburn or gastroesophageal reflux disease (GERD) if the sphincter is not functioning properly.

Regarding the options given in the question, the correct answer is: A. The lower esophageal sphincter prevents the backflow of stomach contents into the esophagus, maintaining a one-way passage from esophagus to stomach.