Phospholipids are usually composed of fatty acids and glycerol. Besides, they may also contain a phosphoric acid, nitrogen bases, and other substituents. Due to the possession of one hydrophilic head and a non-polar tail, they are also called polar lipids. Phospholipids are amphipathic in nature and can be divided into three groups, phosphoglycerides, phosphoinositides, and phosphosphingosides. Among them, phosphoglycerides are major phospholipids which contain glycerol groups linked with both phosphoric acid and fatty acids.
