what is the structure and the purpose of a cell membrane
Cell Membrane. The cell membrane (plasma membrane) is a thin semi-permeable membrane that surrounds the cytoplasm of a cell. Its function is to protect the integrity of the interior of the cell by allowing certain substances into the cell, while keeping other substances out.
Cell Membrane Structure. The cell membrane is primarily composed of a mix of proteins and lipids. Depending on the membraneâs location and role in the body, lipids can make up anywhere from 20 to 80 percent of the membrane, with the remainder being proteins.