1. Active and Passive Transport
7th grade science

2. Have you ever ridden a bicycle down a long hill
Have you ever ridden a bicycle down a long hill? Does it take a lot of energy to go fast?
What about riding a bike uphill? Does it take a lot of energy to go fast?
For a cell, moving materials through the cell membrane through diffusion and osmosis is a lot like riding a bike downhill

3. Passive Transport – is the movement of dissolved materials through a cell membrane without using cellular energy – like riding a bike downhill
2 Methods of Passive Transport:
Osmosis

4. 2. Diffusion

5. Active Transport – is the movement of materials through a cell membrane using cellular energy – like riding a bike uphill
Transport Proteins – these proteins “pick up” molecules outside the cell and carry them in, using energy – ex: calcium, potassium, sodium

6. Transport by Engulfing – the cell membrane surrounds and engulfs, or encloses, a particle. Once the particle is engulfed, the cell membrane wraps around the particle and forms a vacuole within the cell
**Active transport requires the cell to use its own energy, while passive transport does not!**