Amphipathic lipids phosphoglycerides

A. The three major types of amphipathic lipids found in membranes are the gly-cerophospholipids (also called phosphoglycerides), the sphingolipids, and cholesterol. 

Lipids (fats) are generally insoluble in water but are soluble in organic solvents. Solubility characteristics depend on structural features those fats that have no polar residues are least water soluble, and they exist away from the aqueous environments of the organism (e.g., cholesterol esters and triglycerides). Others have hydrophilic along with hydrophobic residues. These are called amphipathic substances (also amphiphiles), and they may exist at the interface between aqueous and nonaqueous environments (e.g., phosphoglycerides). 

Phosphoglycerides are prime examples of amphipathic molecules, and they are the principal lipid components of membranes. The existence of lipid bilayers depends on hydrophobic interactions, as described in Section 4.6. These bilayers are frequently used as models for biological membranes because they have many features in common, such as a hydrophobic interior and an ability to control the transport of small molecules and ions, but they are simpler and easier to work with in the laboratory than biological membranes. 

---