diffusion & osmosis

Diffusion & OsmosisDiffusion & Osmosis

Define Diffusion Define Diffusion

Define DiffusionDefine Diffusion

The movement of molecules from a The movement of molecules from a area in which they are highly area in which they are highly concentrated to a area in which they concentrated to a area in which they are less concentrated. are less concentrated.

-Food Coloring Demonstration-Food Coloring Demonstration

Draw a diagram of an Draw a diagram of an example of diffusion we example of diffusion we

saw in class.saw in class.

Draw a diagram of an example of Draw a diagram of an example of diffusion we saw in class.diffusion we saw in class.

See an animation of See an animation of diffusion here:diffusion here:

http://lewis.eeb.uconn.eduhttp://lewis.eeb.uconn.edu/lewishome/applets/Diffusi/lewishome/applets/Diffusion/diffusion.htmlon/diffusion.html

Define osmosisDefine osmosis

Define osmosisDefine osmosis

The diffusion of The diffusion of waterwater across a across a selectively permeable selectively permeable membranemembrane. .

Define OsmosisDefine Osmosis

    Water moves from a Water moves from a

high concentration high concentration of water (less salt of water (less salt or sugar dissolved or sugar dissolved in it) to a low in it) to a low concentration of concentration of water (more salt or water (more salt or sugar dissolved in sugar dissolved in it).  it). 

http://www.usd.edu/~bgoodman/Osmos.htm

Define osmosisDefine osmosis In this picture a red blood In this picture a red blood

cell is put in a glass of cell is put in a glass of distilled water (all water distilled water (all water with no salt or sugar in it).  with no salt or sugar in it).  Because there is a higher Because there is a higher concentration of water concentration of water outside the cell, water outside the cell, water enters the cell by enters the cell by OSMOSISOSMOSIS.  In this case too .  In this case too much water enters and the much water enters and the cell swells to the point of cell swells to the point of bursting open.  In the end bursting open.  In the end pieces of cell membrane pieces of cell membrane are left in the water. are left in the water.

http://www.usd.edu/~bgoodman/Osmos.htm

See an animation of See an animation of osmosis here:osmosis here:

http://lewis.eeb.uconn.eduhttp://lewis.eeb.uconn.edu/lewishome/applets/Osmos/lewishome/applets/Osmosis/osmosis.htmlis/osmosis.html

Define selectively Define selectively permeable membrane permeable membrane

Define selectively permeable Define selectively permeable membranemembrane

A membrane that allows only certain A membrane that allows only certain materials to cross it materials to cross it

Materials pass through Materials pass through porespores in the in the membranemembrane

For more information on For more information on diffusion & osmosis, click diffusion & osmosis, click

here:here:

http://edtech.clas.pdx.edu/osmosis_thttp://edtech.clas.pdx.edu/osmosis_tutorial/default.htmlutorial/default.html

Why are osmosis & Why are osmosis & diffusion important?diffusion important?

Why are osmosis & diffusion Why are osmosis & diffusion important?important?

All living things have certain requirements they All living things have certain requirements they must satisfy in order to remain alive. must satisfy in order to remain alive.

These include exchanging gases (usually CO2 and These include exchanging gases (usually CO2 and O2), taking in water, minerals, and food, and O2), taking in water, minerals, and food, and eliminating wastes. eliminating wastes.

These tasks ultimately occur at the cellular level.These tasks ultimately occur at the cellular level.

They all require that molecules move through the They all require that molecules move through the membrane that surrounds the cell. membrane that surrounds the cell.

Review Osmosis & Review Osmosis & Diffusion Here:Diffusion Here:

http://wappingersschools.org/WJhttp://wappingersschools.org/WJH/teachers/science/Jim_Site/asigH/teachers/science/Jim_Site/asignments/cells/diffusionetc/diffusinments/cells/diffusionetc/diffusion_osmosis.htmlon_osmosis.html