1. 1.3 Osmosis and Diffusion

2. Diffusion, Osmosis, and the Cell Membrane
Diffusion – is the movement of particles from an area of higher concentration to an area of lower concentration (Ex. Perfume)
Concentration – the amount of a substance in a given space
Osmosis – is the movement of water from an area of higher concentration to an area of lower concentration (Ex. Limp carrot in water) through a selectively permeable membrane

7. Movement across a Membrane
Cell membrane is selectively permeable = only some things in
Cell membrane can be compared to a coffee filter
Diffusion is one way that particles move across the cell membrane
If one side of the membrane has a higher concentration of particles they will move across the membrane until both sides have the same amount = this means an equilibrium is reached
Particles will continue to move back and forth but there will be the same number on either side
Example: oxygen in our cells lungs to the blood cells

8. Reverse Osmosis
Reverse Osmosis – movement of water from a high to a low concentration – backwards – this requires pressure to push the molecules
Used for filtering water, purifying maple syrup and juice, and treating sewage

9. Your Turn Questions P. 49 #1-12
Make sure your lab write up is handed in