part of part of epithelium acellular membrane basement membrane of epithelium AAO:0010596 An acellular membrane that is part of the epithelium, lies adjacent to the epithelial cells, and is the fusion of the the basal lamina and the reticular lamina. FMA:63872 GAID:915 UBERON:0005769 UMLS:C0004799 basement membrane basement membrane of connective tissue membrana basalis this class represents a continuous sheet of basement membrane which can underlie multiple epithelial cells over large regions. In contrast, the GO class 'basal membrane' represents a portion of substance on the scale of a single cell. uberon