SCIENCE|natural and applied sciences|life sciences|biology
- scannán bunaidh Reference Faomhadh an téarma seo mar chuid de Thionscadal Lex
- ga
- basement membrane | basal lamina
- en
- Definition "darkly stained mat-like extracellular matrix that separates cell layers which can be formed by the fusion of either two adjacent basal laminae or a basal lamina with an adjacent reticular lamina of connective tissue" Reference "COM-Terminology Coordination, based on: 'Basement Membrane' (14.4.2021). MeSH."
- Comment The basement membrane (Terminologia histologica: Membrana basalis) is a homogenous layer of the extracellular space located closely beneath basal epithelial cells or membranes of some special types of cells (see below). The name basement membrane derives from light microscopic appearance. Using the electron microscope the following layers of the basement membrane can be distinguished: 1. a Lamina rara externa (or lucida since it is not electron-dense) directly bordering the adjacent cell forms the upper portion of the basal lamina (Terminologia histologica: Lamina basalis) and is 10 to 50 nanometers (nm) thick; 2. [the] next layer is the electron-dense Lamina densa comprising the intermediate part of the basal lamina. It has a thickness of 20 to 300, mostly 50 nm. 3. The following hardly electron-dense Lamina rara interna is only about 10 nm thick and the basal portion of the basal lamina. 4. The consequent Lamina fibroreticularis has a thickness of 200 - 500 nm. In short the basement membrane is comprised of the 3-layered basal lamina and the lamina fibroreticularis.