1. Unit 3: Cells
Cell Transport

3. The Goal of cell transport
Homeostasis
Stable internal conditions*
* Such as temperature and water

4. Passive Transport Definition Types of Passive Transport
Movement across a cell membrane with NO energy
Goes from high to low concentration
Diffusion
Osmosis
Facilitated channels
Ion channels

5. Passive Transport: Diffusion
Definition
Movement from an high concentration to an area of low concentration

6. Passive Transport: Osmosis
Definition
Process of WATER moving from high to low concentration
Hypotonic osmosis: water moves INTO the cell and it swells.
Hypertonic osmosis: water moves OUT off a cell.
The cell shrinks.
Isotonic osmosis: solution and cell are both at homeostasis.

7. Passive Transport: Facilitated Diffusion
Definition
Diffusion with the help of a busser protein
Busser protein

8. Passive Transport: Ion Channel
Definition
Passageway in a membrane for ions* to pass through
Ion = any atom with a charge (+ or -)
Example: sodium (Na + or potassium K+)

9. Active Transport Definition Types of Active Transport
Substances moving across the cell membrane with energy
Goes from low to high concentration
Cell membrane pump
Endocytosis
Exocytosis

10. Active Transport: Cell-Membrane Pump
Definition
Bussers pump molecules across the membrane from LOW to HIGH

11. Active Transport: Endocytosis
Definition
2 types
The process in which cells ingest (take in) molecules
Pinocytosis – cells take in liquids
Endocytosis – cells take in solids

12. Active Transport: Exocytosis
Definition
Cells expel (get rid of) molecules