GENERAL HISTOLOGY

Detailed explanation-1: -The lower esophageal sphincter at the top of the stomach regulates food passing from the esophagus into the stomach, and prevents the contents of the stomach from reentering the esophagus. The pyloric sphincter at the bottom of the stomach governs the passage of food out of the stomach into the small intestine.

Detailed explanation-2: -Four distinct smooth muscle sphincters are present in the GI tract: the lower esophageal sphincter (LES), the pyloric sphincter (PS), the ileocecal sphincter (ICS), and the internal anal sphincter (IAS).

Detailed explanation-3: -The stomach is a ‘j’-shaped organ, with two openings-the oesophageal and the duodenal-and four regions-the cardia, fundus, body and pylorus.

Detailed explanation-4: -The stomach has four major regions: the cardia, fundus, body, and pylorus. The addition of an inner oblique smooth muscle layer gives the muscularis the ability to vigorously churn and mix food.