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(1) Pertains to a molecule containing both polar (water-soluble) and nonpolar (not water-soluble) portions in its structure.

(2) Of, or relating to, a molecule having hydrophobic and hydrophilic regions.


Many biomolecules are amphipathic: phospholipids, cholesterol, glycolipids, fatty acids, bile acids, saponins, etc. In fact, it is the amphipathic nature of phospholipids that they form bilayers in cell membrane. They position their polar groups towards the surrounding aqueous medium whereas their hydrophobic chains towards the inside of the bilayer, defining a nonpolar region between two polar ones.

Word origin: amphi > from the Greek amphis meaning both + pathy > comb. form repr. Greek pátheia, suffering, feeling, equiv. to páth(os) + -ic.

Synonym: amphiphilic.