Intestinal lining
The intestinal mucosa (Latin: mucosa ) is the inner lining of the intestine.
It contains glands that form intestinal juice , certain enzymes that break down nutrients, cells that absorb nutrients from the intestine into the blood and cells that defend themselves against pathogens.
construction
The intestinal mucosa ( tunica mucosa ) is composed of a epithelial layer with a single-layer epithelium ( epithelial lamina mucosae ), a delicate layer of connective tissue ( lamina propria ) and a fine layer of muscle ( Lamina muscularis mucosae established). To increase the surface area, the epithelial cells have a so-called brush border ( microvilli ), which is surrounded by a glycocalyx to protect against self-digestion . The intestinal epithelial cells are also called enterocytes or hem cells .
The intestinal epithelium is with
- the glycocalyx consisting of carbohydrate filaments ,
- Digestive enzymes ( glycoproteins )
- as well as with transport systems located in the membrane
fitted.
Underneath the mucous membrane lies the tela submucosa, a loose layer of connective tissue through which the mucous membrane can be moved relative to the intestinal wall below. It also contains larger blood vessels, nerve fiber bundles, nerves and ganglia ( submucosal plexus ).
function
The food components (in the small intestine ) and water from the intestinal contents (in the large intestine ) are absorbed through the intestinal mucosa . In addition, secretions that are formed by gland cells in the intestinal lining are released into the intestinal lumen.
supporting documents
- ^ A b Matthias Starck: intestinal tract. In: W. Westheide and R. Rieger: Special Zoology. Part 2. Vertebrate or skull animals. Spektrum, Munich 2004, ISBN 3-8274-0307-3 , p. 151.