ABSTRACT
Biological membranes may be considered as of a pair apposed lipid monolayers with proteins intercalated into the hydrophobic core of the monlayers. The freeze-fracture technique owes much to the lipid bilayer arrangement of membranes. Conversely, a major evidence that the structure of biological membranes is a bilayer is the freeze-fracture technique and its interpretation of the fracture plane being in the center of the membrane. In freeze fracture, membrane proteins are visualized as particles on a smooth background representing the acyl tails of the membrane lipids. Much has been said, written, and hypothesized about these lipids. An filipin-cholesterol complex (FCC) as seen through freeze fracture is a local deformation in the contour of the membrane. The creation of such a deformation will push the surface of the membrane into the cytoplasm or into the extracellular space.
