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Large Intestine


Atenodoro R. Ruiz, Jr.

, MD, The Medical City, Pasig City, Philippines

Last full review/revision Oct 2019| Content last modified Oct 2019
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Topic Resources

The large intestine consists of the

  • Cecum and ascending (right) colon

  • Transverse colon

  • Descending (left) colon

  • Sigmoid colon (which is connected to the rectum)

The cecum, which is at the beginning of the ascending colon, is the point at which the small intestine joins the large intestine. Projecting from the cecum is the appendix, which is a small finger-shaped tube that serves no known function. The large intestine secretes mucus and is largely responsible for the absorption of water from the stool.

Locating the Large Intestine

Locating the Small Intestine

Intestinal contents are liquid when they reach the large intestine but are normally solid by the time they reach the rectum as stool. The many bacteria that inhabit the large intestine can further digest some material, creating gas Gas Gas is normally present in the digestive system and may be expelled through the mouth (belching) or through the anus (flatus). There are three main gas-related complaints: Excessive belching... read more . Bacteria in the large intestine also make some important substances, such as vitamin K Vitamin K Deficiency Vitamin K deficiency is most common in infants, especially those who are breastfed. The deficiency can cause bleeding; therefore, all newborns should be given a vitamin K injection. Bleeding... read more , which plays an important role in blood clotting. These bacteria are necessary for healthy intestinal function, and some diseases and antibiotics can upset the balance between the different types of bacteria in the large intestine.

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