1. Moving Cellular Materials Pg. 74-79

2. Passive Transport
A cell’s membrane is semi permeable or selectively permeable which means it allows some things to enter or leave the cell while keeping other things outside or inside the cell.
You could also say that a strainer is semi permeable.

3. Passive Transport
Passive transport is the movement of substances though a cell membrane WITHOUT energy. Substances go with the concentration gradient.
Diffusion is one type of passive transport. It is the movement of molecules from an area where there are more of them to an area where there are less.

4. Passive Transport
Diffusion occurs until equilibrium is reached. This means molecules are equal in both areas.
Osmosis is the diffusion of WATER through a cell membrane.

5. Active Transport
Active transport takes place when energy is used to move materials through a membrane. Substances go against the concentration gradient.
This occurs when a substance is needed in a cell even though the amount inside the cell is already greater then the amount outside.

6. Active Transport
Carrier or transport proteins bind with the needed particle and go through the cell membrane.