Phospholipids

 






A phospholipid is a lipid that contains a phosphate group and is a major component of cell membranes. A phospholipid consists of a hydrophilic (water-loving) head and hydrophobic (water-fearing) tail (see figure below). The phospholipid is essentially a triglyceride in which a fatty acid has been replaced by a phosphate group of some sort.

Phospholipid are amphiphilic molecules with hydrophobic fatty acid chains and hydrophilic moieties. They occur naturally in all living organisms as the major components of cell membranes. Various phospholipid classes with different polar moieties are found in nature. pH greatly affects the association of the polar moieties in phospholipids. When dispersed in water, phospholipids hydrate forming lamellar or hexagonal phases, a behavior which is related to the functions of cell membranes. 


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