1. Types of Cellular Transport
high
low
Weeee!!!
Passive Transport
cell doesn’t use energy
Diffusion
Facilitated Diffusion
Osmosis
Active Transport
cell does use energy
Protein Pumps
Endocytosis
Exocytosis
high
low
This is gonna be hard work!!

2. Passive Transport (HighLow) cell uses no energy
molecules move randomly
Molecules spread out from an area of high concentration to an area of low concentration.
(HighLow)

3. Concentration Gradient
Concentration Gradient - change in the concentration of a substance from one area to another.

4. Passive Transport: 1. Diffusion
Simple Diffusion Animation
Passive Transport: 1. Diffusion
Diffusion: random movement of particles from an area of high concentration to an area of low concentration.
(High to Low)
Diffusion continues until all molecules are evenly spaced (equilibrium is reached)-Note: molecules will still move around but stay spread out.

5. Diffusion
Molecules/ particles in solution tend to slowly spread apart over time. This is diffusion.

6. Diffusion
Movement of molecules from an area of high concentration to an area of lower concentration.
Factors that affect the rate of diffusion: size of molecules, size of pores in membrane, temperature, pressure, and concentration.

7. Diffusion [High] [Low] concentrated, high energy molecules
diffuse, low energy molecules

8. Diffusion will continue until equilibrium is reached
Diffusion will continue until equilibrium is reached. This means there will be an equal distribution of molecules throughout the space. This is why food coloring moves throughout a beaker of water; why odors smell strong at first and then disappear over time.
Equilibrium, a result of diffusion, shows the uniform distribution of
molecules of different substances over time as indicated in the
above diagram.

9. Which molecules will diffuse in each of the figures below?1 2 3 4 5 6

10. ANSWERS 1 2 3 4
No Movement 5 6
No Movement

11. Passive Transport: 2. Facilitated Diffusion
Glucose
molecules
Cellular Transport From a-
High
High Concentration
Cell Membrane
Low Concentration
Protein
channel
Low
Transport Protein
Through a 
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12. Osmosis: the passive transport or diffusion of water through a selectively permeable membrane as a result of a concentration gradient
The direction of water movement across the cell membrane depends on the relative concentrations of free water molecules in the cytoplasm and in the fluid outside the cell.

13. There are three possibilities for the direction of water movement:
Water moves out: When water diffuses out of the cell the cell shrinks. A hypertonic solution where there is a higher concentration of particles in solution outside the cell causes the particle-free water to move outside the cell.
Water moves in: When water moves into the cell, the cell swells. A hypotonic solution where there is a greater concentration of particles in solutions inside the cell causes the particle free water to push into the cell.
No net water movement: Occurs when the fluid outside and inside the cell have equal concentrations of particles in solution. This type of solution is called isotonic