Diffusion & OsmosisOctober 24, 2007Ms. Manaktola

demonstration

Questions:

•What happened?•Why did it happen?

•Microscopic view

diffusion

• Diffusion is the movement of solute molecules from an area of high concentration to an area of low concentration.

• Animation

osmosis

• Osmosis is the passage of water across the membrane from an area of high concentration to an area of low concentration

• Similar to diffusion, but not the same!

• Osmosis only pertains to water molecules

osmosis

• HYPERTONIC and HYPOTONIC are important terms

• When we compare two solutions, a HYPERTONIC solution is the solution with a greater solute concentration relative to the HYPOTONIC solution

• REVIEW: What is a solute?

osmosis

osmosis

• In osmosis, water travels from

HYPOTONIC HYPERTONIC

(less solute) (more solute)

Osmosis and cells

• What do you think will happen if I take a blood cell and place it in a beaker of water?

Osmosis and cells

• What do you think will happen if I take a blood cell and place it in a beaker of very salty water?

Osmosis and cells

Why do your fingers wrinkle when you’ve

been in the pool?

Your homework!

Your ticket out the door

• On the provided diagram, make a diagram to illustrate diffusion and osmosis. Label if necessary.