Filtration, diffusion, and osmosis

A report on Filtration, Diffusion, and Osmosis

1. Filtration, Diffusion, and Osmosis Jo Patrick Mabelin BS Biology 3

2. Diffusion Movement of particles Concentration of substances differ from one point to another High concentration to Low concentration

3. Factors affecting diffusion rate through a membrane temperature - ↑ temp., ↑ motion of particles molecular weight - larger molecules move slower steepness of concentrated gradient - ↑difference, ↑ rate membrane surface area - ↑ area, ↑ rate membrane permeability - ↑ permeability, ↑ rate

4. Membrane Permeability Diffusion through lipid bilayer Diffusion through channel proteins Cells control permeability by regulating: Number of channel proteins Opening or closing gates

5. Osmosis Flow of water through selectively permeable membrane From: Side of higher water concentration To: Side of lower water concentration Movement from lower solute concentration to higher solute concentration

6. Aquaporins : Channel proteins in the plasma membrane specialized for the passage of water Cells increase rate of osmosis by installing more aquaporins

7. Osmotic Pressure Amount of hydrostatic pressure to stop osmosis Osmosis Slows due to hydrostaitc pressure

8. Filtration Water molecules and extremely small solutes are forced to move through a selectively permeable membrane by a hydrostatic pressure

9. Tonicity ability of a solution to affect fluid volume and pressure in a cell depends on concentration and permeability of solute

10. Hypotonic Solution High solvent concentration Cells absorb water, swell, and may burst

11. Hypertonic High solute concentration Cells lose water and shrivel

12. Isotonic Concentration of solute and solvent are level No changes in cell volume and shape