1. Diffusion Vs. Osmosis
Biology

2. Definitions Diffusion: Osmosis:
Movement of molecules from a place where there is a large amount (high concentration) to a place where there is none or a smaller amount (low concentration).
Osmosis:
Diffusion of water across a selectively permeable membrane

3. Diffusion Diagram High Concentration Low Concentration Beginning
Equilibrium

4. Osmosis Diagram
Selectively Permeable Membrane: Some substances can pass through and some cannot.

5. 3 Types of Solutions where OSMOSIS can take place
1. ISOTONIC – amounts of water are equal inside and outside of the cell (EQUILIBRIUM)
93%
93 % %
93%

6. 3 Types of Solutions where OSMOSIS can take place
2. HYPERTONIC – amount of water inside the cell is greater than outside of the cell. (CELL SHRINKS)
85%
85% %
93%

7. 3 Types of Solutions where OSMOSIS can take place
3. HYPOTONIC – amount of water inside the cell is less than outside of the cell. (CELL EXPANDS)
98%
98% %
93%

8. Osmosis & Cell Wall
Cell wall is a rigid membrane, how is it affected by osmosis?