Lower digestive tract

Lower digestive tract builds on top of that mechanically processed food and spend.

The lower portion then is intended to absorb nutrients from the chyme. This occurs most intensively in the small intestine to increase the absorptive surface of the intestine, is provided with villi, mikrokly. Mixing movements chyme makes contact with the intestinal wall and the peristaltic movements of her shift intestine.

In the small intestine, its two sections (jejunum and ileum), a length of 3-5 meters, are absorbed electrolytes – thus the ions, minerals sodium, calcium, chloride, potassium, iron, water and also both types of vitamins, i.e. water-soluble and fats. Further absorption of nutrients are digested carbohydrates. Only absorbable monosaccharides – simple sugars. Final cleavage disaccharides takes place on the surface of intestinal cells (enterocytes). Neither protein is wasted, however, they must be digested into amino acids and di- and tripeptides. Fats (lipids) are absorbed as a fatty acid di- or monoglycerides, while itself directly diffuses unesterified cholesterol through the intestinal wall. After passing through the small intestine digesta waits journey through the colon (ascending colon, tranversum, descending, sigmoid, rectum). Colon length of about 1.5 meters is designed to shape the stool, which is then eliminated. Even here there occurs absorption of some components of the chyme, mainly water and electrolytes. The large intestine is the place of production of vitamin K, which consists of commensal intestinal bacteria – gut microflora. Intestinal microflora helps to spend many nutrients – eg. Vegetable fiber prevents the overgrowth of pathological bacteria, mold. The last section of the digestive system – rectum is then tasked to form and eliminate stool.

In addition, digestion is digestive system and immune function. In the intestines is found GALT, a lymphatic tissue of the intestines. The most important part is the appendix or wormlike projection of the small intestine.