Diffusion and Osmosis Webquest
Name_______________________
1. Go to this website from Ohio State about diffusion. Remove the cap from the perfume, what do you notice about the particles as they spread out? This is another website which shows diffusion, click anywhere on the tab to restart the process. As you watch the particles move, how do you know when equilibrium has been reached? When equilibrium has been reached, do the particles stop moving?
2. This is a website about osmosis. The red line down the middle represents the cell membrane. The blue are the water molecules. What do you notice about the green and red molecules? Do all substances fit through the cell membrane?
3. Watch this animation of osmosis. What happens to the number of molecules on each side of the cell membrane (the line down the middle) when “no net flow” is reached?
Diffusion Worksheet – Use chapter three in your textbook to answer the following.
1. Use arrows to indicate the direction of diffusion in each case: is a molecule that can pass through the cell membrane. is a cell membrane.
A) B)
2. For each of the situations below use an arrow to indicate the net movement of sugar into or out of the cell. (Assume that the sugar molecules can pass through the cell membrane in each case.)
3. The cell membrane is made of a ___________________ ______________________.
4. The cell membrane is _________________permeable. This means that ____________ ______________________________________________________________________.
5. Diffusion always causes particles to move from a region of _______________ concentration to a region of ______________ concentration.
6. Does a cell expend energy when molecules diffuse in or out of the cell?