Describing a molecule that contains both polar (i.e. hydrophilic) and nonpolar (i.e. hydrophobic) parts. Many biomolecules are amphipathic, including glycolipids, phospholipids, and cholesterol. They tend to orientate with their hydrophilic part in an aqueous environment and their hydrophobic part shielded from the water, as in micelles and lipid bilayers, whose properties are a fundamental feature of cell membranes.