1. Essential Standard Bio.1.2 Analyze the cell as a living system.
Cell Transport
Essential Standard
Bio.1.2 Analyze the cell as a living system.

2. Cell Transport Movement of materials across cell membrane 2 Types:
Passive Transport
Active Transport

3. Passive Transport
Movement of substances across membrane without input of energy until equilibrium is reached
With concentration gradient; high to low concentration
4 Types
Diffusion
Osmosis
Facilitated Diffusion
Ion Channels

4. Active Transport
Movement of substances across membrane requiring input of energy
Against concentration gradient; low to high concentration
3 Types
Protein Pumps
Endocytosis
Exocytosis

5. Passive Transport - Diffusion
Movement of molecules
Molecules are in constant motion
Moves “down” concentration gradient
Rate of diffusion depends on
Size of molecule
Type of molecule

6. Passive Transport - Osmosis
Diffusion of water
Direction of osmosis depends on concentration of solutes on both sides of membrane
Hypotonic solution
Cytolysis
Hypertonic solution
Plasmolysis
Isotonic solution

7. Osmosis Problems
A cell which is 98% water is placed into a solution of 10% sucrose. What is the direction of the water movement?

8. Osmosis Problems
A cell has 45% sodium concentration and is placed in a solution of 55% water concentration. What is the direction of the water movement?

9. Passive Transport – Facilitated Diffusion
Diffusion of larger molecules
Use carrier proteins (integral)
No energy required

10. Passive Transport – Ion Channels
Regulate flow of ions across membrane
Ion-specific!
Ions requiring ion channels: Na+, K+, Ca+, Cl-

11. Active Transport – Protein Pumps
Carrier protein that transports molecules against concentration gradient

12. Active Transport - Endocytosis
Large particles are engulfed into the cell
Pinocytosis – “cell drinking”
Phagocytosis – “cell eating”

13. Active Transport – Exocytosis
Large particles exit the cell