1. OSMOSIS AND SURFACE AREA TO VOLUME RATIO

2.  The net movement of atoms, ions or molecules down a concentration gradient.  Movement is from: High Low

4.  Are molecules moving after equilibrium is established?

5.  There is no net movement of materials.  When the concentration is equal on both sides.  **different from equilibrium of reaction (in chemistry) where the rate of the forward rxn=rate of reverse rxn

6.  Diffusion of water.  Water moving from an area if its high concentration to an area of its low concentration.  No cell energy is used.

7.  Solute CANNOT cross membrane  Concentration of water outside the cell relative to the water inside the cell. 1. Isotonic (same) 2. Hypotonic (higher [H 2 O] OUTSIDE the cell) 3. Hypertonic (higher [H 2 O] INSIDE the cell)

8. Predict the NET movement of WATER for each solution *The membrane does not allow the solute to pass through the membrane Hypotonic – net movement into the cell Isotonic – no net movement Hypertonic – net movement out of the cell

10.  What happens when you drink salt water?  What would the effect be of increasing the amount of salt in oceans on marine life?

12. Why Are Cells So Small? Cell volume to surface area ratios favor small size. Nucleus to cytoplasm consideration (control). Metabolic requirements. Speed of diffusion.