GENERAL HISTOLOGY

Detailed explanation-1: -The one at the top of the esophagus is called the upper esophageal sphincter (UES) and the one at the bottom of the esophagus (which separates the esophagus from the stomach) is called the lower esophageal sphincter (LES). The area in between is known as the body of the esophagus.

Detailed explanation-2: -At the junction between the stomach and esophagus is the lower esophageal sphincter. This muscular sphincter acts as a valve that normally keeps food and stomach acid in the stomach, and prevents the stomach’s contents from regurgitating back into the esophagus.

Detailed explanation-3: -The lower esophageal sphincter (LES) is a bundle of muscles at the low end of the esophagus, where it meets the stomach. When the LES is closed, it prevents acid and stomach contents from traveling backwards from the stomach.

Detailed explanation-4: -The intrinsic component of the LES consists of esophageal muscle fibers and is under neurohormonal control. The extrinsic component consists of the diaphragmatic crura and the phrenoesophageal ligament, which provide anatomical support to the LES and further protection against gastric reflux.

Detailed explanation-5: -Abstract: The upper esophageal sphincter (UES), also known as the pharyngoesophageal segment (PES), is a 4-cm segment of the digestive tract that separates the esophagus from the pharynx and larynx.