What is the Large Intestine?

Steve R.

Part of the digestive system, the large intestine is an organ that, if stretched out, would extend 5 feet (about 1.5 m) in length. The organ is responsible for collecting waste not digested in the small intestine. While the small intestine is actually larger in length, the large intestine receives its name for its width, which stands at about 2.5 inches (about 6.4 cm) thick. This organ stores waste until it is ready to be ejected from the body, and is made of various sections including the cecum, colon, rectum, and anal canal.

A diagram showing diseases in the colon, which makes up the majority of the large intestine.
A diagram showing diseases in the colon, which makes up the majority of the large intestine.

Located in the right quadrant of the abdominal cavity, this organ is the next stop in the digestive process after the small intestine. Once food arrives in the intestine, the majority of digestion has already occurred. What remains in the organ is fiber, dead cells discarded from the coating of the intestines, salt, bile pigments, and water.

The rectum is a portion of the large intestine.
The rectum is a portion of the large intestine.

Inside the organ, water and electrolytes, including sodium and chlorine, are discarded from food. Useful bacteria aid in the digestion process. The bacteria create vitamins that are consumed by the blood and help with assimilating fiber.

The large intestine is responsible for collecting waste not digested in the small intestine.
The large intestine is responsible for collecting waste not digested in the small intestine.

A small sac about 2 inches (about 5 cm) in length, called the cecum, forms the first section of this intestine. The cecum connects the small intestine with the colon. This area is responsible for taking in and storing processed food from the small intestine and moving it along to the colon. Usually the cecum contains undigested food, traces of water, vitamins, and minerals. The appendix is attached to the cecum.

The large intestine holds waste until it is ready to be ejected from the body.
The large intestine holds waste until it is ready to be ejected from the body.

The largest part of the intestine is the colon. The colon is actually made of four sections: the ascending colon, transverse colon, descending colon, and sigmoid colon. Inside the colon, fiber, water, and vitamins combine with mucus and bacteria. When water is removed from the mixture, solid waste called feces forms. As the solid waste moves along the colon, the lining soaks up water and minerals which provides nourishment for the cells.

The large intestine serves as the largest section of the digestive system and contains the cecum, colon, and rectum.
The large intestine serves as the largest section of the digestive system and contains the cecum, colon, and rectum.

The final 8 inches (about 20 cm) of the large intestine is known as the rectum. Inside the rectum, remaining waste gathers, causing the area to expand. The last 1 inch (about 3 cm) of the rectum is the anus canal. Fecal matter is expelled through the anus during a bowel movement.

An ultrasound may be used to detect problems with the sigmoid colon.
An ultrasound may be used to detect problems with the sigmoid colon.

You might also Like

Readers Also Love

Discuss this Article

Post your comments
Login:
Forgot password?
Register: