1. Cell Membrane/Plasma Membrane Structure
Lecture #10

2. Plasma Membrane
Boundary that separates the living cell from it’s non-living surroundings.
Phospholipid bilayer
Amphipathic - having both:
hydrophilic heads
hydrophobic tails
~8 nm thick
Head: alcohol and phosphate group
Tail: fatty acids
Phospholipid

3. Phospholipids can move laterally and allow water and other small molecules to pass through into or out of the cell. 
This process is called diffusion which requires no energy because water molecules are moving with the concentration gradient, and not against.

4. Fluid-Mosaic Model

5. Plasma Membrane
Cholesterol is a lipid located in the plasma membrane which adds fluidity and flexibility to the bilayer

6. Proteins—For Function
Transport
Receptors
Enzymes
Signal Transducers
Support

7. Plasma Membranes Proteins aid in diffusion and cell recognition
Peripheral proteins are found only on one side of the membrane
Integral proteins = Membrane proteins
Lipids or Carbohydrates use proteins to help move across cell membranes
carbohydrate chains called glycoproteins attached to help cells in recognize each other and certain molecules.

8. Plasma Membrane Proteins
PROTEINS CAN MOVE IN THE MEMBRANE, TOO!

10. Membrane Functions Protection Communication
Selectively allow substances in
Respond/Recognize the environment