Diffusion and Osmosis

Unit 4 Life Science

1. What is Diffusion?

Movement of molecules from an area of high concentration to an area of low concentration.

2. What causes diffusion?

Random movements of molecules.

3. What is the Kinetic Theory of

Matter?All matter is made up of small particles that are in constant motion.

4. What is Osmosis?

The movement of water through a semi-permeable membrane.

5. What is “semi-permeable”?

Material or membrane that will let some things pass through but not all things.

6. What is Active Transport?

Movement of molecules through a membrane that DOES require energy Imagine pushing a

rock up a hill, it requires ENERGY!

7. What is Passive Transport?

Movement of molecules through a membrane that DOES NOT require energy. Think of yourself

floating down a lazy river…it does not require energy!

8. How are Active and Passive Transport

different?Active transport requires energy and passive does not.

Passive transport move molecules in the same direction and Active moves in the opposite direction.