How Organisms Respond To Changes In Their Environment

Carmella Gordon Farragut High School
2345 S. Christiana
Chicago, Il. 60620


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.


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


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?


Bridging the learning experience, is man being affected by environmental
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