EXERCISE 104 



Every living cell and every living organism must get out of its protoplasm the injurious by-products 

 of metabolism ; but different organisms accomplish this result in different ways. 



In the following table indicate in what ways the plants and animals named get rid of their wastes, 

 pointing out first their resemblances and then their distinctive structures and activities. 



RESEMBLANCES AND DIFFERENCES OF VARIOUS ORGANISMS 

 WITH RESPECT TO EXCRETION 



RESEMBLANCES 



DISTINCTIVE STRUCTURES AND PROCESSES 



Diphtheria 

 bacillus 



Earthworm 



Frog 



Questions. 1. In what respects does excretion resemble respiration? 



2. In what respects do these two processes differ ? 



3. In what ways can wastes be made harmless to the organism besides expelling them from the system > 



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