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Vermiform appendix
Arteries of cecum and vermiform appendix. (Appendix visible at lower right, labeled as 'vermiform process').
Normal location of the appendix relative to other organs of the digestive system (anterior view).
Details
System	Digestive
Identifiers
Latin	appendix vermiformis
MeSH	D001065
TA98	A05.7.02.007
TA2	2976
FMA	14542
Anatomical terminology[edit on Wikidata]

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. The term vermiform comes from Latin and means "wormlike in appearance". The cecum is the first pouch-like structure of the colon. The appendix is near the junction of the small intestines and large intestines.

Size and location

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

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.

Function

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

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 in these people.

One explanation has been that the appendix is a remnant of an earlier function, with no current purpose. (Note, however, that the pineal gland, which only recently (around 1960) was found to produce important chemicals such as melatonin, was once similarly considered a vestigial structure.)

Diseases

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

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

References

1. Guinness world record for longest appendix removed.

External links

• "The vestigiality of the human vermiform appendix: A Modern Reappraisal" -- evolutionary biology argument that the appendix is vestigial
• A professor of physiology claims the appendix has a known function

• Organs
• Digestive system