Cell membrane also called the plasma membrane. The external limiting membrane of a cell. It is composed of lipids (fat molecules) that have a hydrophobic (insoluble in water) end and a hydrophilic (water-soluble) end. Cell membranes are made of lipid bilayers in which the lipids line up in two layers with the hydrophobic ends facing each other and the hydrophilic ends facing the outside and the inside of the cell. |
