BIO 12 UNIT 2: Study Notes

TRANSPORT ACROSS THE CELL MEMBRANE

TRANSPORT TYPES

1. PASSIVE: does not need ATP energy


1. Diffusion: movement of molecules across the membrane from an area of high [ ] to low [ ] {ex. CO2 and O2 in lungs + body tissues} (between phospholipids)
2. Osmosis: movement of water molecules (diffusion of water) across the membrane from an area of high [ ] to low [ ] (water has its own carrier protein)
3. Facilitated: diffusion (high to low []) with the aid of a carrier protein {ex. Glucose sugars in small intestine}


2.  ACTIVE: uses ATP energy
1. Active: use of a transport protein that helps molecules move against the concentration gradient (low to high [ ]); needs ATP energy
2. Endocytosis and Exocytosis [described later...]   

VIDEO TIME...

• Passive transport-->  http://www.youtube.com/watch?v=JShwXBWGMyY
• Active Transport -->  http://www.youtube.com/watch?v=STzOiRqzzL4&feature=results_video&playnext=1&list=PL22852FE67A13AEC7