A model for the structure of cell membranes based upon the hydrophobic properties of interacting phospholiplids. The polar head groups face outward to the solvent, whereas the hydrophobic tails face inward. Proteins (p) are embedded in the bilayer, sometimes being exposed on the outer surface, sometimes on the inner surface, and sometimes penetrating both surfaces. The proteins exposed on the outer surfaces of cells commonly serve as distinctive antigenic markers. Membrane proteins may serve a variety of functions such as communication, energy transduction, and transport of specific molecules across the membrane. See fluid mosaic concept.
Subjects: Genetics and Genomics.