Where is the stomach?

Structure and function of the stomach and duodenum

From an anatomical point of view, you can see the stomach like a croissant lying diagonally in the upper abdomen. Next to the Stomach entrance(Gastric mouth, cardia) the upper end forms a dome-shaped bulge, the Bottom of stomach(Gastric fundus). The biggest part makes the Stomach body(Corpus) that goes down to the Antrum(Porter anteroom) narrowed. The lower end contains the Stomach doorman(Gastric outlet, pylorus), which is the transition to the Duodenum(Duodenum) and acts as a sphincter muscle.

Anatomical overview of the stomach and duodenum. The bile empties into the duodenum via the bile duct and the pancreatic juice (pancreas) via the pancreatic duct. In most people, both ducts unite immediately in front of the mouth in the pancreatic papilla.
Gerda Raichle, Ulm

During digestion, the stomach wall contracts again and again, moves the chyme back and forth and finally pushes it further towards the exit of the stomach by means of peristaltic waves. The food is chopped up further and further and, under the action of gastric juice, prepared for chemical digestion, which then takes place in the small intestine. Numerous glands and cells in the stomach lining make up the Gastric juice. It contains hydrochloric acid, which kills pathogens, enzymes for protein digestion (pepsin and its inactive precursor Pepsinogen), Mucous substances that protect the gastric mucosa and the Intrinsic factor(Intrinsic factor), a protein compound that is necessary for the absorption of vitamin B12.

Food stays in the stomach for different lengths of time. While water leaves the stomach after about 20 minutes, solid food remains in the stomach until the individual parts are less than 3 mm in diameter. This can take several hours. Of the various food components, the fats stay in the stomach the longest and the carbohydrates the shortest.


Dr. med. Arne Schäffler, Dr. Bernadette Andre-Wallis | last changed on at 10:36