EXERCISE 20 



Problem. What do animal cells look like when viewed through the microscope ? 



What to use. Microscope ; slides ; cover slips ; prepared slides of various tissues, scraping from 

 lining of mouth, gills from clam, or drop of water from hay infusion. 



What to do. Examine several different animal cells, preparing as in previous exercise. 



Record. Make careful drawings of several different kinds of animal cells ; label parts of cell that 

 were noted in the plant cell. 



Questions. 1. In what ways may cells differ from each other? 



2. In what ways do the animal cells studied differ from the plant cells ? 



3. Why, do you suppose, were plant cells discovered nearly two hundred years before animal cells ? 



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