Cell membrane in animals is composed mainly of the molecule of :

Chemically, the plasma membrane or cell membrane is made up of $60 \%$ proteins and $40 \%$ lipids. The percentage of carbohydrates ranges from 1-10 which are in the form of glycoproteins or glycolipids. Proteins may be extrinsic (peripheral) and intrinsic (integral) while lipids may be phospholipids, glycolipids and sterols.