1. 1 ACTIVE TRANSPORT ACROSS A MEMBRANE

2. Overview of Active Transport Active Transport 1. Carrier Protein 2. Endocytosis3. Exocytosis

3. Active Transport - Single Molecules 1. Carrier Protein: same as facilitated diffusion, but cell energy used to move molecule across membrane against the concentration gradient (from low to high) lower concentration outside higher concentration inside

4. Active Transport Steps: 1. Solute (i.e. amino acid, vitamin, glucose) binds to carrier protein. 2. Carrier protein uses energy (ATP) to flip over & releases solute molecule to other side of the membrane. 3. Carrier protein flips back to get another solute molecule. LOW CONCENTRATION HIGH CONCENTRATION

5. Active Transport - Bulk Transport 2. Endocytosis (two types): phagocytosis: (cell eating) large particles, whole cells or solids enter the cell enter as a food vacuole pinocytosis: (cell drinking) bulk transport of dissolved solutes or fluids into the cell enter as a vesicle Note: In both processes, the cell membrane wraps around the material being brought into the cell.

6. Bulk Transport - Phagocytosis food particle cell membrane food vacuole

7. Active Transport 3. Exocytosis: bulk transport of solutes or fluids out of the cell

8. Bulk Transport - Exocytosis This diagram is showing the same process as the last slide.

9. Cell Transport Overview Single Molecules facilitated diffusion protein channel

10. Video

11. Homework page 71 # 1 – 6