adventitia

(noun)

The outermost layer of connective tissue encasing a visceral organ or vessel.

Related Terms

Examples of adventitia in the following topics:

  • Lymphatic Vessel Structure

    • The outermost layer is the adventitia, consisting of fibrous tissue.
    • Larger lymph vessels have many more layers of adventitia than do smaller lymph vessels.
    • The smallest vessels, such as the lymphatic capillaries, may have no outer adventitia.
    • As they proceed forward and integrate into the larger lymph vessels, they develop  adventitia and smooth muscle.
    • Blood vessels also have adventitia, sometimes referred to as tunica.

  • Submucosa

    • Under these muscle layers is the adventitia, layers of connective tissue continuous with the omenta.

  • Serosa

    • Serosa is not to be confused with adventitia, a connective tissue layer which binds together structures rather than reducing friction between them.

  • Overview of Hemostasis

    • Blood vessel with an erythrocyte (red blood cell) within its lumen, endothelial cells forming its tunica intima or inner layer, and pericytes forming its tunica adventitia (outer layer).
    • Microvessel showing an erythrocyte (E), a tunica intima of endothelial cells, and a tunica adventitia of pericytes.

  • Development of the Heart

    • Blood vessel with an erythrocyte (red blood cell) within its lumen, endothelial cells forming its tunica intima or inner layer, and pericytes forming its tunica adventitia (outer layer).

  • Serous Membranes

    • Serosa is not to be confused with adventitia, a connective tissue layer which binds together structures rather than reducing friction between them.

  • Microscopic Anatomy of the Stomach

    • Under these muscle layers is the adventitia, layers of connective tissue continuous with the omenta.

  • Blood Vessel Structure

    • The outermost layer is the tunica externa or tunica adventitia, composed entirely of connective fibers and surrounded by an external elastic lamina which functions to anchor vessels with surrounding tissues.

  • Lymphatic Capillaries

    • Unlike larger lymphatic vessels, lymphatic capillaries do not contain smooth muscle nor do they have a well developed adventitia, only small elastic filaments that perform a similar function.