Clinically, the mouth to the duodenum is called the upper digestive tract, and the jejunum to the anal canal is called the lower digestive tract. You mean the lower digestive tract. Adult small intestine is 5-7 meters long and large intestine is 1.5 meters long.
The small intestine is an important part of digestion and absorption. The function of the large intestine is to absorb water from food residues, secrete mucus and excrete feces.
Shimi reaches the cecum beauty through the ileocecal valve for about 500-1000 ml in 24 hours. It mainly absorbs water and sodium in the right half of the colon. It can absorb 400 ml of sodium and 350-2000 ml of water daily.