Diffusion Osmosis Diffusion The movement of molecules from

Diffusion & Osmosis

Diffusion The movement of molecules from an area in which they are highly concentrated to an area in which they are less Concentrated. u requires NO ENERGY.

Concentration How crowded the solute is in the solution u If the solute is more crowded then the concentration is higher. u If the solute is more spread out then the concentration is lower.

Diffusion of Perfume in the classroom Who smelled the perfume first? Who smelled it last?

Diffusion of Food Coloring in Water How did the temperature of the water affect the speed of diffusion? How could you explain this observation?

Osmosis u The diffusion of water across a semi - permeable membrane. u Requires NO ENERGY.

Semi-Permeable Membrane u. A membrane that allows only certain materials to cross it Water u Water passes through pores in the membrane

Osmosis Video http: //highered. mcgrawhill. com/sites/0072495855/student_vi ew 0/chapter 2/animation__how_osmos is_works. html

Movement of Water u Why does water move from less concentrated solution to the more concentrated solution?

Isotonic Solution u. A solution that causes no change in the size of the cell u Why do you think it causes no change in the size of the cell?

Hypertonic Solution u Has more dissolved particles outside the cell then inside the cell u Meaning: Hyper: more than normal u Tonic=Dissolved particles u u. A solution that causes a cell to shrink because of Osmosis.

Hypotonic Solution u Has less dissolved particles outside the cell then inside the cell u Meaning: Hypo: less than normal u Tonic=Dissolved particles u u. A solution that causes a cell to swell because of Osmosis.

Summary u u u Diffusion is the movement of molecules from an area of higher concentration to an area of lesser concentration. Osmosis is the movement of water thru a semi-permeable membrane. Both do not require NO ENERGY!