Trabecula 977221 208458279 2008-04-27T03:57:12Z 222.153.45.101 [[WP:UNDO|Undid]] revision 208166373 by [[Special:Contributions/137.164.227.136|137.164.227.136]] ([[User talk:137.164.227.136|talk]]) A '''trabecula''' (plural '''trabeculae'''. From [[Latin]] for '''small beam'''.) is a small, often microscopic, [[biological tissue|tissue]] element in the form of a small [[Beam (structure)|beam]], [[strut]] or [[Rod (geometry)|rod]], generally having a mechanical function, and usually but not necessarily composed of dense [[collagen]]ous tissue. On [[histological section]], a trabecula can look like a [[septum]], but in [[Three-dimensional space|three dimensions]] they are topologically distinct, with trabeculae being roughly rod or pillar-shaped and septa being sheet-like. Trabeculae are usually composed of dense fibrous tissue, i.e. mainly of [[collagen]], and in most cases provide mechanical strengthening or stiffening to a soft solid organ, such as the [[spleen]]. They can be composed of other materials, such as [[bone]] or [[muscle]]. When crossing fluid-filled spaces, trabeculae may have the function of resisting tension (as in the [[penis]]) or providing a cell filter (as in the [[eye]].) Multiple perforations in a septum may reduce it to a collection of trabeculae, as happens to the walls of some of the [[pulmonary alveolus|pulmonary alveoli]] in [[emphysema]]. ==Examples of trabeculae== * [[Cancellous bone|trabeculae of bone]] * [[trabeculae of corpora cavernosa of penis]] * [[trabeculae of corpus spongiosum of penis]] * [[trabecular meshwork of the eye]] * [[trabeculae of spleen]] * [[trabeculae carneae]] * [[septomarginal trabecula]] ==Etymology== Diminutive form of Latin ''trabs'', which means a beam or bar. In the 19th century, the neologism ''trabeculum'' (with an assumed plural of ''trabecula'') became popular, but is less etymologically correct. ''Trabeculum'' persists in some countries as a synonym for the [[trabecular meshwork]] of the [[eye]], but this can be considered poor usage on the grounds of both etymology and descriptive accuracy. ==External links== * {{eMedicineDictionary|Trabecula}} [[Category:tissues]] [[de:Trabekel]] [[pt:Trabécula]]