What are the intestinal villi?

The inner walls of the small intestine of the human being are covered with a number of threads, tubular projections called intestinal villi. These finger -like projections, although small, are very complex and serve as places for absorption of the necessary nutrients and fluids into the body. To help in this process, Villi increases the surface area of ​​the small intestine, which makes nutrients easier. In this way they play a key role in proper digestion. Each cluster extends approximately 0.04 inches (about 1 mm) to the lumen, an empty chamber inside the small intestine. Inside each clot you can find a capillary bed and a lymphatic blood vessel. Outsides Villi are covered with cell layers. The nutrients pass through certain cells in this layer, the capillary network and lymphatic vessels are occupied and are therefore transported by blood and the lymphatic system to the rest of the body.

cell types that cover the intestinal villi surfaces include ripe absorption cells of enterocytes, cells of mucus secretary cups and antimicrobial panet cells. EntErocyte cells are covered with microvilli, allowing cells to absorb nutrients. Cells that cover Villi live for only a few days. When the cells die, they are thrown into lumen, cleaved and absorbed into the body.

There are areas called crypts, which are ditch structures that produce cells found on the surface of the villa. On the foundations of the crypts there are stem cells and to replace dying cells, stem cells constantly divide and create daughter cells continuously. While some of these daughter cells remain stem cells, most migrate villi and divide into other types of cells. Some become ripe absorbent enterocytembuňky, while others become cup -producing mucus cells. Other migrant cells become paeth cells whose task is to sterilize the interior of the small intestine by secreting antimicrobial peptides.

Thanks to the intestinal villi is a surface area tEncumeal intestines much larger than any person would guess. It is about 656 square feet (200 square meters) - that is 100 times the surface area of ​​the human skin. Without the intestinal villi, the human body could not absorb the nutrients necessary for survival.