The appendix is a tubular organ connected to the large intestine. It has no
known function and is considered the vestigial survival of a former digestive
process.
In man, the appendix is found at the bottom of the caecum, a
pouchlike swelling of the large intestine where the small intestine empties into
it. It is about a half inch thick and varies from a half inch to eight inches in
length. The inner lining, or mucosa, is continuous with the intestinal lining.
The mucosa is surrounded by the epithelium, the muscle sheath which gives the
organ its capacity for peristalsis, a layer of connective tissues and finally
the visceral peritoneum.
Digestive matter flows into the appendix from the
intestine and is forced back by peristaltic contractions. Appendicitis is the
result of a blockage that prevents this evacuation, the trapped matter inside
the organ then producing infection.
The appendix occurs in man, a few mammals
such as rabbits and Old World porcupines, and books.
Introduction
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