How Organisms Respond To Changes In Their Environment

Carmella Gordon             Farragut High School
                            2345 S. Christiana
                            Chicago, Il. 60620
                            312-542-3000

Objective: 

To observe the reaction of living cells to mechanical and chemical stimuli.

To observe the streaming of protoplasma in living cells.

To identify the relationship between cell response and survival.

Materials: 

       Living culture               Compound Microscope            
       Droppers                     Salt crystals
       Vinegar                      Microscope slides and coverslips
       Decaffeinated coffee         Caffeinated coffee
       Sugar                        Cotton fibers
       Specimen pipettes

Strategy:  

1.  Using a specimen pipette, remove a drop from the collected specimen.
                         
2.  Place culture on the microscope slide and cover.  Focus microscope
    to locate organism.

3.  Having observed the normal activity, some artificial stimuli will
    be introduced so that the cell response can be observed.
    Record observed behavior on chart provided.
 
4.  Prepare a new culture specimen if necessary; repeat strategies 1-2.

5.  Cautiously place a small salt crystal near some of swimming organisms.
    Observe and record their response.

6.  Continue to add each stimuli along side of covered organism.
    Observe and record the behavior of the organism. 

7.  Observe movement.  Are new structures visible on the organism?
    Has movement stopped?
    
Conclusion:
    
     Bridging the learning experience, is man being affected by environmental 
pollutants?