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Internet Biology/Active and Passive Transport-Answer Key

http://www.biologycorner.com/bio1/diffusion.html

 

Define the following terms:

 

A)        Passive Transport

Passive Transport is the movement of of molecules from an area of high concentration to an area of low concentration.  No energy is required.  Diffusion and Osmosis are two types of passive transport.

 

            1)         Diffusion

Diffusion is the process in which molecules spread from an area of high concentration to an area of low concentration.  A good example of diffusion would be to stand on one side of a room and spray perfume on the other side of the room.  Eventually the molecules would diffuse to the other side of the room.

 

            2)         Osmosis (click on start animation)

Osmosis is the same as diffusion except that it deals with water molecules that move across a membrane.  A good example of osmosis would be to stand on one side of a room and spray perfume on the other side of the room.  Eventually the molecules would diffuse to the other side of the room.

           

B)        Types of Solutions (remember the salt is the solute)

                       

1)        Isotonic-Sketch example

            Concentration is equal on both sides.

 

            Sketched example will vary, check site for accuracy.

 

2)        Hypotonic-Sketch example

There is less salt on the outside of the cell which will cause the water molecules to move     into the cell.  Cell is at risk for bursting.

 

            Sketched example will vary, check site for accuracy.

 

3)        Hypertonic-Sketch example

There is more salt outside the cell which will cause the water molecules to move outside the cell  and shrink.

 

            Sketched example will vary, check site for accuracy.

 

 

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