|plasmalemma, Also called: plasma membrane a very thin membrane, composed of lipids and protein, that surrounds the cytoplasm of a cell and controls the passage of substances into and out of the cell|
cell membrane n.
The semipermeable membrane that encloses the cytoplasm of a cell. Also called cytomembrane, plasmalemma, plasma membrane.
The thin membrane that forms the outer surface of the protoplasm of a cell and regulates the passage of materials in and out of the cell. It is made up of proteins and lipids and often contains molecular receptors. The membranes of organelles within the cell are made of the same basic material as the cell membrane. In plant cells, the cell membrane is surrounded by a rigid cell wall. Also called plasma membrane. Compare cell wall. See more at cell.