What is the nature of the phospholipid bilayer?

• Hydrophilic phosphate head faces the water so is in contact with the aqueous environment. Polar

  2 hydrophobic fatty acid tails repels water so is not in contact with the aqueous environment. Non polar

  Non polar molecules can diffuse in the hydrophobic region
• Intrinsic proteins can be channel proteins, carrier proteins and active enzymes.

  Extrinsic proteins move alot, enhances stability of cell membrane.

  Glycolipids act as antigens.

  Glycoproteins act as receptors.

  Cholesterol maintains fluidity of membrane because it affects the movement of the phospholipids.