How are proteins classified according to mosaic manner?

-Peripheral or extrinsic proteins, weakly attached to outer polar surface of lipid bilayer. Peripheral or extrinsic proteins that are tightly attached to inner and outer surfaces of lipid bilayer via lipid molecules, covalently bonded to a phospholipid. -Integral or Intrinsic proteins that penetrate the membrane partially through one layer (monotopic) or two layers (polytopic) by means of one or more helix segment, most abundant, must have at least one stretch rich in hydrophobic aa to stablize in hydrophobic region of lipid bilayer, whom usually adopt a helix shape,