Anatomy of Human stomach

Stomach

Shape and location

            It is J-shaped organ that is present just below diaphragm at the left side of abdomen. It is the dilated part of alimentary canal.

Portion of stomach

There are two portions of stomach

Cardiac portion

              It is present immediately after oesophagous.Cardiac sphincter is a opening that separates stomach from oesophagous.This opening is surrounded by muscles.

Pyloric portion

             Pyloric portion is a chamber present just below cardiac portion. Pyloric sphincter is a opening surrounded by muscles that separates this portion from duodenum.

                                  

Gastric glands

These glands are present in the three walls of stomach which secretes gastric juice.

Composition of gastric juice

·         This juice contains mucus, hydrochloric acid and an enzyme called pepsinogen which is converted into pepsin by HCl.

·         In food, microorganisms are killed by HCl. Protein portion of food is partially digested into polypeptides and short peptide chains by pepsin.

                           Through a process of churning food is further break down in stomach. The contraction and relaxation of stomach walls help in thoroughly mixing of gastric juice and food. Heat is also produced by the churning process that helps in melting activity of lipids contents present in food particles. Then food is converted into soup like mixture called chime.Aftr this, little mass entered into duodenum by the opening of pyloric sphincter.