Fluid Mosaic Model of Membrane Structure
A special feature of the lipid bilayer is that it is a fluid and not solid. Therefore, portions of the membrane can literally flow from one point to another along the surface of the membrane.
This combination of flexibility and rigidity is maintained by incorporation of a mixture of unsaturated and saturated phospholipids into the cell membrane.
The effect is a membrane that is both ordered and disordered. Membranes are orderly, in that they consist of two layers of phospholipid molecules, all of which are standing at right angle to the surface of the membrane.
Membranes are disorderly in that within the bilayer lipid molecules are free to jostle about like people in a crowd. Such a structure is called a liquid crystal.
The above described mosaic disposition of membrane proteins, in conjunction with the fluid mosaic model for membrane structure, membrane been enveloped e+ depin e- volume of cells.
Fluid mosaic model by S. J. Singer and G. L. Nicolson in 1972 in this model, e- lipid proteins are assumed to be mobile, so e+ e- can move rapidly and literally in e- plane and e- membrane.