1. Membranes
Permeability

2. Cell membranes
A boundary between the inside of the cell and the outside environment
Three main types of membranes
Permeable
Semi permeable
Non-permeable

3. Membrane Types Permeable Membrane Semi permeable Membrane
Allows the passage of most materials through a membrane
Semi permeable Membrane
Allows only specific materials through the the membrane
Non-permeable Membrane
Does not allow any passage through membrane

4. Plasma Membrane A semi permeable membrane that surrounds animal cells
Controls the flow of materials in and out of the cell
Nutrients
Oxygen
Carbon Dioxide
Water

5. Fluid Mosaic Model Composed of a bi-layer of lipids
Fluid -> moveable
Mosaic -> More than one thing
put together
These lipids have 2 ends
Hydrophillic water liking
Hyrdophobic water fearing
Hydro means water
Phobic means fear
Phillic means liking

6. Plasma Membrane Con’t
The two different ends of the lipid molecules line up to form a double layer called a lipid bi-layer
This structure allows
Easy movement of the
membrane
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