Phospholipid

Phospholipids are a class of lipids that are a major component of all cell membranes. They can form lipid bilayers because of their amphiphilic characteristic. The structure of the phospholipid molecule generally consists of two hydrophobic fatty acid "tails" and a hydrophilic phosphate "head", joined together by a glycerol molecule. The phosphate groups can be modified with simple organic molecules such as choline.