Vermiform appendix

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Image:Gray536.png Image:Stomach colon rectum diagram.gif In human anatomy, the vermiform appendix (or appendix, pl. appendixes or "appendices") is a blind ended tube connected to the cecum ('caecum' in British English). It develops embryologically from the cecum. In adults, the appendix averages 10 cm in length but can range from 2-20 cm. The diameter of the appendix is usually less than 7-8 mm. While the base of the appendix is at a fairly constant location, the location of the tip of the appendix can vary from being retrocaecal to being in the pelvis to being extraperitoneal. In most people, the appendix is located at the lower right quadrant of the abdomen. In people with situs inversus, the appendix may be located in the lower left side.

Currently, the function of the appendix, if any, remains controversial in the field of human physiology.

Hypothesized functions for the appendix include lymphatic, exocrine, endocrine, and neuromuscular functions. However, most physicians and scientists believe the appendix lacks significant function, and that it exists primarily as a vestigial remnant of the larger cellulose-digesting cecum found in our herbivorous ancestors. Some people note, however, that the pineal gland which only recently (around 1960) has been found to produce important chemicals like melatonin was once considered a "vestigial remnant" as well.

An operation to remove the appendix is an appendicectomy (also appendectomy).

The most common diseases of the appendix (in humans) are appendicitis and carcinoid.

The longest appendix ever removed was that of a Pakistani man on June 11, 2003, at Pakistan Institute of Medical Sciences, Islamabad, Pakistan, measuring 23.5 cm (9.2 in) in length. Template:Ref

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Congenital absence of the appendix

There have been cases of people who have been found, usually on laparoscopy or laparotomy, to have a congenital absence of their appendix. There have been no reports of impaired immune or gastrointestinal function.

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