The functions and roles of the large intestine mainly include the formation, storage and excretion of feces, secretion, and maintenance of the stability of the internal environment of the body.
1. Formation, storage and excretion of feces: the large intestine receives food residues from the small intestine, and forms feces after absorbing excess water, electrolytes, and other substances such as ammonia and bile acids, and then passes the feces through peristaltic movement of the large intestine to the end of the large intestine and excretes them out of the body through the anus.
2. Secretory function: the colon can secrete colonic fluid, in which the mucin secreted by the cup-shaped cells has the function of protecting the mucous membrane and lubricating the feces, which makes the feces easy to go down, and at the same time protects the intestinal wall to avoid mechanical damage.
3. Maintaining the stability of the body’s internal environment: the colon contains a large number of bacteria, bacteria can produce a variety of enzymes, which can make the decomposition of sugars, fats, proteins and cellulose and other substances, and thus maintain the relative stability of the body’s internal environment.