Haustra
Encyclopedia
The haustra of the colon
Colon (anatomy)
The colon is the last part of the digestive system in most vertebrates; it extracts water and salt from solid wastes before they are eliminated from the body, and is the site in which flora-aided fermentation of unabsorbed material occurs. Unlike the small intestine, the colon does not play a...

 are the small pouches caused by sacculation
Sacculation
Sacculation in terms of anatomy is the formation of a pouch in various organs ....

, which give the colon its segmented appearance. The taenia coli
Taenia coli
The taenia coli are three separate longitudinal ribbons of smooth muscle on the outside of the ascending, transverse, descending and sigmoid colons. They are visible, and can be seen just below the serosa or fibrosa....

 runs the length of the large intestine. Because the taenia coli is shorter than the intestine, the colon becomes sacculated between the taenia, forming the haustra.

Haustral contractions are slow segmenting movements that occur every 25 minutes. One haustrum distends as it fills, which stimulates muscles to contract, pushing the contents to the next haustrum.

There is a wider distance between haustra than between the circular folds
Circular folds
The circular folds are large valvular flaps projecting into the lumen of the bowel.-Composition:...

 of the small intestine
Small intestine
The small intestine is the part of the gastrointestinal tract following the stomach and followed by the large intestine, and is where much of the digestion and absorption of food takes place. In invertebrates such as worms, the terms "gastrointestinal tract" and "large intestine" are often used to...

, and the haustra don't reach around the entire circumference of the intestine, in contrast to circular folds of the small intestine that do. These differences can assist in distinguishing the small intestine from the colon on an abdominal x-ray
Abdominal x-ray
An abdominal x-ray is an x-ray of the abdomen. It is sometimes abbreviated to AXR, or KUB .-Diagnostic Tool:...

.

Loss of haustra is a sign of chronic ulcerative colitis
Ulcerative colitis
Ulcerative colitis is a form of inflammatory bowel disease . Ulcerative colitis is a form of colitis, a disease of the colon , that includes characteristic ulcers, or open sores. The main symptom of active disease is usually constant diarrhea mixed with blood, of gradual onset...

.

External links

- "Intestines and Pancreas: Large Intestine"
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK