Abdomen-Visible Human

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The inner surface of the small intestine contains many convoluted into finger-like projections called villi. The increased surface area helps the body absorb and process digested foods. The small intestine is divided into three regions, the duodenum which follows the stomach, jejunum, and ileum. Each segment has specific functions regarding digestion.

Most of the carbohydrates from a meal are absorbed in the duodenum. This segment of intestine also plays an important role in the absorption of minerals such as iron and calcium, and vitamins such as vitamin D. Brunner's glands in the duodenum secrete bicarbonate ion which help neutralize the acid of the stomach. Also with the duodenum, the common bile duct and the pancreatic duct release digestive enzymes and bile into the lumen of the small intestine.

Bile is a thick green fluid secreted by the liver and stored in the gall bladder. It contains bile acids which help the gut absorb fats. Bilirubin - a breakdown product of heme (associated with hemoglobin in red blood cells) gives bile its color.

The jejunum follows the duodenum and continues absorbing sugars and amino acids from digested protein.

The ileum is the most distal segemnt of the gut. This region plays an important role in abosrbing fats and fat-soluble vitamins such as vitamins A, E, and K.

Key points in this image
kidney | colon | small intestine | erector spinae | psoas major | quadratus lumborum | oblique muscles | rectus abdominus |
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Module Name: a_vm1640
Module Title: Abdomen-Visible Human
Image Info: Transverse section through the abdomen
Created by: Lynn Bry
Contact Email:bryl@medicine.wustl.edu
Last modified: Feb 2nd, 1997 introduction=This transverse sectiion lies approximately 5cm above the umbilicus (belly button). Note the posterior location of the kidneys, and their encasement in the perirenal fat. Segments of small intestine and colon may also be seen. Small bowel can be distinguished from the colon by it's narrower bore, and smaller lumen. This particular section cuts through the ascending colon, seen on the right, the transverse colon, located in the middle, and the descending colon shown posteriorly on the left side of the body. Click on 'colon' in the key points listed below to have these features outlined in the image.

Muscles of interest include the psoas major and quadratus lumborum muscles, the erector spinae muscles of the back, and the muscles of the anterior abdominal wall: external and internal obliques, transversus abdominus, and rectus abdominus muscles.

Created with Annotation 1.0