What is the colon?

The colon is a five-foot-long muscular tube that is a part of the large intestine within the gastrointestinal system, responsible for absorbing water and salt from food matter. The colon also serves as a storage place for waste matter. The colon has four sections:
The first section is called the ascending colon. It starts with a small pouch (the cecum) where the small bowel attaches to the colon and extends upward on the right side of the abdomen. The cecum is also where the appendix attaches to the colon.The second section is called the transverse colon since it goes across the body from the right to the left side in the upper abdomen.The third section, the descending colon, continues downward on the left side. The fourth and last section is known as the sigmoid colon because of its “S” or “sigmoid” shape.

The colon, or large intestine, is a tube-like organ connected to the small intestine at one end and the rectum at the other. The colon removes water and some nutrients and electrolytes from partially digested food. The remaining material, solid waste called stool, moves through the colon to the rectum and leaves the body through the anus.

Picture of Parts of the Colon
The colon is also known as the large intestine. It is the final portion of your gastrointestinal (GI) system, which starts in the mouth and ends with the rectum. The colon is divided into four parts, and these are called the ascending, transverse, descending and sigmoid colon. It is responsible for absorption of fluids and electrolytes as well as compacting stool. Many diseases can be associated with the colon, including malabsorption, chronic inflammation and cancer, which is why good overall health and diet as well as screening for diseases of the colon is important.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.