Diffusion & Osmosis: Concepts and Examples

1. Diffusion & Osmosis Ch 8

2. Diffusion Definition: Net movement of particles from an area of _______ concentration to an area of ______ concentration Example: _____________________________ high low The smell of popcorn traveling across the room

3. Diffusion results from the _________ movements of particles (Brownian motion) • Diffusion is a ________ process random SLOW

4. rate • 3 factors affect the ________ (how quickly or slowly) of diffusion • ________________ If you increase ________ then ______________________ • ________________ If you increase ________ then __________________________ • ________________ If you increase ________ then _______________________ Temperature Temp. it will move more Conc. Concentration it will diffuse more rapidly Pressure Pressure it will increase diffusion

5. Eventually… the particles will become _______ distributed • The condition in which there is continuous movement, but no overall concentration change is called __________________ evenly dynamic equilibrium

6. The difference in concentration of a substance across a space is called _______________________ concentration gradient High concentration concentration gradient Low concentration

7. In the case with diffusion, particles are moving from an area of _____ concentration to an area of _____ concentration; therefore, the substance is said to move ______ the concentration gradient. high low with

8. Another example of diffusion: Oxygenin the air sacs of lungsdiffuses into capillaries Particles constantly move & bounce off each other and other surfaces

11. Osmosis Definition: Diffusion of water across a _________________ membrane Osmosis is a special example of __________ Semi-permeable diffusion

12. Osmosis Example: Absorption of water by plant roots

13. Osmosis • It is important to notice that __________________ molecules do not cross the membrane, but _______ molecules do cross during osmosis • Osmosisoccurs in both plant and animal cells and there are three conditions that typically appear. large impermeable H20

14. same • Isotonic Solution • Concentration of dissolved substances in the solution is the _______ as the concentration of dissolved substances inside the cell. • Hypotonic solution • Concentration of dissolved substances is _______ in the solution outside the cell than the concentration inside the cell • Hypertonic solution • Concentration of dissolved substances is ________ outside than the concentration inside the cell less greater

15. ISOTONIC SOLUTION 10% salt HYPOTONIC SOLUTION cell 10% salt 2% salt HYPERTONIC SOLUTION cell 10% salt 25% salt cell 10% salt

16. SALT SUCKS

17. ISOTONIC SOLUTION 10% salt HYPOTONIC SOLUTION cell 10% salt 2% salt HYPERTONIC SOLUTION cell 10% salt 25% salt cell 10% salt Equal movement in and out More H2O in than out More H2O out than in

18. Here is what happens when more water exits or more water enters