2 Function Allows nutrients to pass into and out of the cell. Maintains homeostasis.
3 StructureComposed of a phospholipid bilayer called the fluid mosaic model.
4 Structure Structure of phospholipid bilayer: Each phospholipid contains a glycerol backbone, 2 fatty acid chains, and a phosphate group.A phosphate is formed by replacing one fatty acid in a lipid with a phosphate group.
5 Structure Structure of phospholipid bilayer: Each phosphate group has two fatty acid tails that are nonpolar and one head containing a polar phosphate group.The nonpolar tails stop water-soluble molecules form moving through the membrane.The polar head interacts with the watery environment inside and outside the cell.
6 Structure The phospholipid bilayer also contains: Cholesterol Transport ProteinsProteinsCarbohydrates
7 Structure Function of cholesterol: Function of transport proteins: Stabilizes the membrane by preventing the fatty acid tails from sticking together.Function of transport proteins:Span the entire membrane to move substances through the plasma membrane.
8 Structure Function of carbohydrates: Stick out of the surface of the cell along with proteins in order to identify chemical signals.Function of proteins at inner surface:Attach the plasma membrane to the internal support structure of the cell.Give flexibility.