The large intestine is about 1.5 m long and its diameter is about 50 mm. It consists of two main parts: colon and rectum. A small intestine passes into a intraperitoneal pouch called a caecum (or appendix), i.e. the first part of the colon. The colon then ascends to the right side of the body, passes under the ribs, then descends to the left side.
Rectum (the final part of the large intestine) is a short tube (about 120 mm long), extending from the end of the colon to the anus. Through the membrane wall of the column liquids and mineral salts are absorbed into the bloodstream, while the indigestible solid substances are pressed into the rectum where they – feces – are deposited until the body expels them through the anus.
The colon is particularly susceptible to inflammation due to infection, and is more susceptible (compared to other parts of the digestive tract) to the development of tumors and polyps. In addition, the food that is being eaten by most Europeans and North Americans has a negative effect on the colon and on the teeth, so the colon and rectal diseases are much more frequent in that part of the world than in Africa and Asia.