1. In Da Club - Membranes & Transport: Crash Course Biology #5 (11:14)

2. The Cell Membrane Aka Plasma Membrane Controls what enters and leaves the cell Phospholipid Bilayer

3. Passive and Active Transport No energy required Material moves against the concentration gradient Material is too large to pass through plasma membrane Energy required Material moves down the concentration gradient

4. Diffusion is the movement of particles from high to low concentration Diffusion

5. Osmosis – Diffusion of water across the cell membrane Isotonic – Equilibrium reached Hypertonic – Less water, more solute Hypotonic – More water, less solute S S S S S S S S S W W W W W W W W W W W W W W W W W W W W W W W W Osmosis

6. Figure 5.13-2 Hypotonic solution Hypertonic solution Sugar molecule Selectively permeable membrane Osmosis Isotonic solutions Osmosis

7. Figure 5.14 Animal cell Plant cell Normal Flaccid (wilts) Lysing Turgid (normal) Shriveled Plasma membrane H2OH2O H2OH2O H2OH2OH2OH2O H2OH2O H2OH2O H2OH2O H2OH2O (a) Isotonic solution (b) Hypotonic solution (c) Hypertonic solution

9. Diffusion through carrier proteins Specialized doors/windows through the plasma membrane Primarily for molecules like sugar too large to pass through the plasma membrane Only allow specific material through Facilitated Diffusion

10. Pumps material across the plasma membrane Moves material “up” the concentration gradient Moves material through specific carrier proteins Requires energy to “pump” Molecular Pump Lower solute concentration Higher solute concentration ATP Solute

11. Exocytosis discharges material from the cell via transport vesicles Endocytosis accepts material into the cell via transport vesicles http://www.psc.edu/science/2007/bardomain/images/endocytosis.jpg http://www.college-cram.com/study/biology/files/-1/113/exocytosis.gif Endo- & Exo- cytosis Movement of very large molecules

12. Figure 5.UN03 Passive Transport (requires no energy) Active Transport (requires energy) DiffusionFacilitated diffusionOsmosis Higher solute concentration Lower solute concentration Higher water concentration (lower solute concentration) Lower water concentration (higher solute concentration) Solute Higher solute concentration Lower solute concentration ATP Solute Water Solute MEMBRANE TRANSPORT