ANATOMY

Detailed explanation-1: -In the stomach several mucosal defence mechanisms protect the stomach against hydrochloric acid and noxious agents. The pre-epithelial protection is made up by the mucus-bicarbonate barrier. Mucus and bicarbonate, secreted by mucus cells, create a pH gradient maintaining the epithelial cell surface at near neutral pH.

Detailed explanation-2: -The intestinal mucus is an efficient system for protecting the epithelium from bacteria by promoting their clearance and separating them from the epithelial cells, thereby inhibiting inflammation and infection.

Detailed explanation-3: -The stomach is protected from self-digestion by the mucosal barrier. This barrier has several components. First, the stomach wall is covered by a thick coating of bicarbonate-rich mucus. This mucus forms a physical barrier, and its bicarbonate ions neutralize acid.

Detailed explanation-4: -The inner surface of the stomach is lined by a mucous membrane known as the gastric mucosa. The mucosa is always covered by a layer of thick mucus that is secreted by tall columnar epithelial cells.

Detailed explanation-5: -Mucous Cells SMs that line the stomach lumen and the GPs have a columnar shape and secrete an alkaline, highly viscous mucous substance rich in bicarbonate ions that helps to protect the stomach mucosa from abrasive food particles and erosive gastric acid.