Structure and Function of the Colon

The colon is one of the more well-known organs in the gastrointestinal system. The colon is essentially just another term for the large intestine. The structure and function of the colon are very important to your ability to digest food and excrete waste. This article we’ll take a look at the structure of the colon and some of its more important functions.

Structure of the colon

The colon is located in your lower abdomen. It begins at the end of the small intestine, at a junction known as the ileocecal junction. The small intestine drains the food which is being processed into an area known as the cecum. The cecum is the first part of the large intestine, although it is technically not considered part of the colon. Surgeons and anatomists love picking on medical students over a detail like that. The appendix is also located in this area.

The first part of the actual colon is known as the a sending colon. The ascending colon is approximately 5 to 8 inches long and a couple of inches in diameter. As the name implies, the ascending colon points upward. This portion of the colon is located on the right side of your abdomen.

When the a sending colon reaches the liver, it turns left. This area is known as the hepatic flexure. The colon then travels across your abdomen. This area of the colon is known as the transverse colon. The transverse colon is attached to the lower portion of your stomach.

When the transverse colon reaches the left side of your abdomen, it turns downward. The downward portion of your colon is known as the descending colon. At the end of the descending colon there is a short segment known as the sigmoid colon. It gets this name from being approximately S-shaped.

The entire colon is approximately 1 1/2 meters, or four to five feet in length.

Function of the colon

Unlike other parts of your gastrointestinal system, the colon is not primarily responsible for the absorption of food and nutrients.

The primary function of the colon is to reclaim water so that it is not wasted when you go to the bathroom. Maintaining proper water balance in the body is a key function of the colon. The colon also serves to store waste before it is excreted.

The colon does have some minor role in the absorption of some nutrients. For example, it is responsible for observing some vitamins, specifically vitamin K.

Being at the end of the gastrointestinal system, most of the nutrients and water that have been eaten are already absorbed by the time they reach the colon. Approximately 90% of all nutrients and water have already been dealt with by your body before they reach the colon. Much of the content of the colon is often indigestible food and fiber.

Your colon contains a large number of bacteria which are mixed with these indigestible foods. The bacteria help down some of the fiber, concentrating your feces and getting the last remaining bits of nutrition out of the food. It is important to note that actual chemical digestion does not take place in the colon. All enzymes that are responsible for breaking down food have already been secreted, primarily in the small intestine and duodenum.

The colon is a major organ in the body, without which you would not live long. Unfortunately, it is susceptible to several diseases, such as diverticulosis, cancer, Chron’s Disease, and many others. As far as structure and function are concerned, the colon is relatively simple compared to many other organs.