The cell’s outer membrane made up of a two layers of phospholipids with embedded proteins. It separates the contents of the cell from its outside environment, and it regulates what enters and exits the cell.
In animals the plasma membrane is the outermost covering of the cell whereas in plants, fungi, and some bacteria it is located beneath the [[cell wall].
Word origin: plasma: from Greek, from plassein, to mold.
Synonym: cell membrane, plasmalemma.
See also: fluid mosaic model.