Fluid Mosaic model

Describe how the cell membrane is both a container and semi-
permeable barrier

• cell membrane holds all cell’s content together, keeping internal living environment from external environment

• Controls what molecules go in or out of the cell to help maintain homeostasis

Major way proteins associate with membranes

non-covalent interactions with different amino acids, lipids, and water

What do we mean by fluid mosaic model?

we’re talking about the membrane bilayer because its components act like a fluid

How does cholesterol regulate membrane fluidity?

• At high temp, cholesterol reduces fluidity stopping membrane frmo becoming too permeable

• At low temp, cholesterol disrupts the phospholipids frmo packing too tightly, which maintains permeability

• Cholesterol acts as a buffer to resist changes in permeaility