Dictionary Definition
User Contributed Dictionary
English
Etymology
From the lang=la.
Noun
- anatomy histology The outermost layer of epithelial tissue encasing a visceral organ.
Related terms
Extensive Definition
For example, the connective tissue that surrounds
an artery is called the
tunica adventitia because it is considered extraneous to the
artery.
To some degree, its role is complementary to that
of the serosa, which also provides a layer of tissue surrounding an
organ. In the abdomen, whether an organ is covered in adventitia or
serosa depends upon whether it is peritoneal or retroperitoneal:
- peritoneal organs are covered in serosa (a layer of mesothelium, the visceral peritoneum)
- retroperitoneal organs are covered in adventitia (loose connective tissue)
In the gastrointestinal
tract, the muscularis
externa is bounded in most cases by serosa. However, at the
thoracic esophagus,
ascending colon, descending colon and the rectum, the muscularis
externa is instead bounded by adventitia. (The muscularis externa
of the duodenum is
bounded by both tissue types.)
The connective tissue of the gallbladder is covered by
adventitia where the gallbladder bounds the liver, but by serosa for the rest
of its surface.
See also
External links
- - "Mammal, whole system (LM, Low)"
- (vermiform appendix)
- (uterus)
- (vagina)
adventitia in German: Tunica adventitia
adventitia in Japanese: 外膜
adventitia in Thai:
ชั้นแอดเวนทิเทีย