1. Osmosis

2.  Energy requirements?  No energy required  Modes of passive transport?  Diffusion through cell membrane  The movement of a substance from higher concentration to lower concentration  Facilitated Diffusion  Diffusion through the cell membrane via a channel protein Passive Transport Review

3. Osmosis A mode of diffusion  Osmosis: the movement of water from a higher concentration to a lower concentration  “The Diffusion of water through a semi- permeable membrane”

4. Results of Osmosis 1.Isotonic Solution- The water and solute concentration are in equal concentrations on the inside and outside of the cell  Equilibrium has been reached

5. Results of Osmosis 2. Hypotonic Solution- The concentration of solute outside the cell is “less than” the concentration of solute inside the cell  So, there is more water outside the cell  Water moves into the cell  This causes cell expansion, and perhaps, bursting.  Called Lysis

6. Results of Osmosis 3. Hypertonic Solution- The solute concentration outside the cell is “higher than” the solute concentration inside the cell  Water concentration is greater inside the cell  Water moves out of the cell  Cell will shrivel, shrinking in size  Called crenation