Temperature affects cell membrane permeability. At high temperatures, proteins that support and maintain cell membranes may be denatured, increasing membrane permeability.How may membrane permeability change at low temperatures?

It is important that a cell membrane is intact as it protects cell contents from the external environment, and controls what can enter and exit the cell. At temperatures below normal, cell membrane permeability may will initially reduce due to increased rigidity of fatty acid chains, preventing movement of proteins and other molecules in the cell membrane. If the temperature is further reduced, this will have the same affect as a high temperature by denaturing the proteins and therefore increasing permeability.Proteins may be integral, spanning the phospholipid bilayer that makes the cell membrane. These act as efficient transporters and may be selective for certain molecules and ions. Peripheral proteins are attached to the ends of integral proteins and aid their function. The Fluid Mosaic Model is used to describe the structure of cell membranes, as various molecules come together to produce an efficiently functioning cell membrane.Inefficient transport links to diseases such as alzheimers, where plaques in the phospholipid bilayer block efficient communication between cells.