Difference Between the Small and Large Intestines

What is the difference between the small intestine and large intestine? What do they do?


Although they have different names, the small and large intestines is actually a continuous tube. They, however, differ in both structure and function.

The small intestine and large intestines are parts of the digestive tract or also called alimentary canal. The digestive tract is a long, continuous tube, which starts from the mouth and ends in the anus. It consists of the mouth, pharynx, esophagus, stomach, small intestine, large intestine, and the anus.

The Digestive System. The intestines are part of the digestive system.Small Intestine

The small intestine, or small bowel, is a long tube where food coming from the stomach pass through. This is where most of the food particles are broken down or digested and nutrients are absorbed to be used by the body. It is divided into several portions namely: the duodenum (firs part), jejunum, and ileum (last portion).

After taking the nutrients from the food, the food particles then move to the large intestine.

Large Intestine

The large intestine is the tube where feces or stool is found. It contains the undigested food and some fluids. The large intestine has four main regions. They are the cecum, colon, rectum, and anal canal. Major functions of the large intestine include:

 Production of some B vitamins and vitamin K, which is produced by good bacteria normally living in the large intestine.

 Absorption of some water, vitamins, and salts or ions.

 Bowel movement: What remains after “absorption” is stool, which passes from the colon into the rectum and out of the anus.

Stool in the large intestine is prevented from going back into the small intestine through a valve called the ileocecal valve.

Suggested Readings

National Digestive Diseases Information Clearinghouse (NDDIC), National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). NIH Publication No. 05–5120, February 2005

Tortora, G. and Grabowski, S.: PRINCIPLES OF ANATOMY AND PHYSIOLOGY. 10th ed. John Wiley and Sons, Inc., 2003.

Image Credit: NIDDK Image Library

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