Seen from the outside, the stomach looks like a dilated tube.
He can use it to let the food pass through the shortest route or to store it for some time.
If you look into the stomach, for example with the help of an endoscope (gastroscopy), you can see a rough fold of the mucous membrane. The folds run mostly in the direction of the food path and thereby form the so-called Stomach roadon which liquids can pass so quickly.
- Esophagus - Esophagus
- Incision at the stomach entrance -
- Stomach entrance -
- Gastric dome -
- Stomach body -
- Great curvature of the stomach -
horizontal part -
Duodenum, pars horizontalis
- Duodenum, upper part -
Duodenum, pars superior
- Stomach porter - Pylorus
- Small curvature of the stomach -
- Stomach folds - Plicae gastricae
You can find an overview of all Dr-Gumpert images at: medical illustrations
Structure of the stomach and mucous membrane
But the fine structure of the gastric mucosa is particularly important for the tasks and functions of the stomach.
More on the subject: Tasks of the stomach
All organs of the digestive tract through which the food travels, the so-called hollow organs, are very similar in their wall structure.
All consist - from the inside out - of a mucous membrane, a surrounding muscle layer and a connective tissue skin that is adjacent to the abdominal cavity. The actual gastric mucosa is in turn divided into three layers. Starting from the inside, these are:
- the Lamina epithelialiswhich contains mucus and acid producing cells
- the Lamina propria, in which there are glands whose function and structure differ depending on their location in the stomach, and
- the Lamina muscularis, a layer of muscle that allows the other two layers to stretch and contract again.
The actual glands in the lamina propria are close to the next outer layer, the lamina muscularis. There are cells that make hormones and those that make enzymes that start to break down food components.
In the glandular neck, which conducts the secretion into the stomach, there are also cells that release hydrochloric acid, which creates the acidic environment in the stomach, and cells that produce a neutralizing mucus.
The cells of the superficial mucous membrane, the lamina epithelialis, also produce a tough and fat-rich mucus, which is supposed to coat the mucous membrane and thus protect it from the aggressive acid.
Differences in the gastric mucosa in different sections
The gastric lining shows Differences in structure and function, depending on the location.
At the Stomach entrance is for example a lot of slime produced, as well Lysozyme, a defense against bacteria.
in the Bulk of the stomach takes up most of the Acid production and thus the actual digestion takes place. Also be here Digestive enzymes added, which break down fats, for example, in order to make the process even more effective and targeted.
At the Gastric outlet becomes a lot again mucus formed, which makes the food pulp less acidic and thus already on the further way through the Intestines prepared in which a more alkaline environment prevails.
Function of the gastric mucosa
After esophagus food gets into the stomach, which is one of the first stages of digestion.
Its job is not to extract individual substances from food, but rather these To make substances more accessible for the subsequent digestive steps.
In addition, possible pathogens, a certain number of which are inevitably ingested with food, should be rendered harmless. This creates the lining of the stomach by excreting Lysozyme (see above) and through the production of hydrochloric acid, which inside the stomach for a pH value of 2 and thus for a very acidic environment cares.
Through the tough layer of mucus, which acts as a protective coat, create the cells of the gastric mucosa neutral milieu (pH = 7) and protect yourself from the damaging effects of the acid.
This equilibrium is prone to failure. Inflammation or, for example, alcohol consumption can lead to an excess of acid and thus to a Damage to the lining of the stomach to lead.
Learn more about: Tasks of the stomach