Small intestine how does it work

Intestinal mucosa is composed of villi, as well as cells that produce chemicals that help digestion and produce hormones that help to control the digestive process of the small intestine, pancreas, and gallbladder. One function of the small intestine is to coordinate many of its activities, including peristalsis.

It does this because the small intestine has a highly integrated nervous system, called the enteric nervous system. This is what keeps the intestinal contents moving along the intestinal tract for proper digestion and absorption of nutrients. Common conditions associated with the small intestine include:.

Note, many conditions of the small intestine can impact the villi, resulting in malabsorption of nutrients. The various treatment modalities for disorders of the small intestine include:.

Many common tests are used to diagnose conditions of the small intestine. These include:. Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. MUSC Health. Small intestine. Colorado State University Vivo Pathophysiology.

Gross and micro anatomy of the small intestine. Collins JT, Badireddy M. Anatomy, abdomen and pelvis, small intestine. Updated August 11, Small bowel atresia, intestinal atresia. Cochrane WJ. Overview of digestive tract birth defects. Merck Manual Consumer Version. Updated April MedLine Plus. Small intestine disorders. Updated September 22, Your Privacy Rights.

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Was this page helpful? Thanks for your feedback! Skip to navigation menu Skip to content. High Priority Alert. Close alert. Informational Alert. The small intestine has three parts:.

Duodenum The duodenum is the first part of the small intestine. Ileum The ileum is the third part of the small intestine. Jejunum The jejunum is the second part of the small intestine. Also in This Section…. Contact Us. Stories of Discovery. Milestones in Cancer Research and Discovery. Biomedical Citizen Science. Director's Message. Budget Proposal.

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