CHAPTER III 

 LIVING THINGS AND THE ENVIRONMENT 



Problems : What is " being alive "f 



What are tropismsf 



Of what value are tropisms to a living thing f 



What are adaptations f 



In what respects has man modified his environment? 



Laboratory Suggestions 



Home work. The study of a living plant and a living animal. List functions, 

 likenesses, differences. 



Demonstration of some tropisms, plant and animal. 



Field trip. Visit to a museum or botanical garden or zoological park for 

 the study of habitat groups. 



A study of some simple adaptations. 



A survey to discover how man has modified his environment. 



A Living Plant and a Living Animal compared. — A walk in the 

 fields or a vacant lot on a day in early autumn will give us first- 

 hand acquaintance with many common plants which, because of 

 their ability to grow under somewhat unfavorable conditions, are 

 called weeds. Such plants as the dandelion, butter and eggs, and 

 shepherd's purse, are particularly well fitted by nature to produce 

 many of their kind, and also are able to thrive under conditions 

 which would not easily support life in other less hardy plants. 

 Feeding on these and other plants, are several kinds of animals, 

 most of them insects. 



If we attempt to compare, for example, a grasshopper with the 

 plant on which it feeds, we at once see several points of likeness 

 and of difference. Both plant and insect are made up of parts, 

 each of which, as the stem of the plant, or the leg of the insect, 

 appears to be distinct, but is a part of the whole living plant or 

 animal. These parts, such as the leaves of the plant, or the legs of 

 the insect, are used by the plant or the animal for definite purposes, 



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