SURVEY QUESTIONS 



What do we mean by "being alive"? Why do plants and animals 

 turn toward or away from the source of light ? Are they affected by other 

 factors of their environment ? Could you name some things that all living 

 things can do ? What is meant by the term " adaptation " ? 



UNIT II 



WHAT IS BEING ALIVE? THE FUNCTIONS OF LIVING 



THINGS 



Preview. We have seen in our study of elementary science, 

 several differences between living and non-living matter. Water, 

 for example, when cooled sufficiently, becomes ice, or, if heated 

 to the boiling point, becomes vapor. In order to be changed it 

 has to be acted upon by outside forces. But when a plant or an 

 animal grows, or moves, or in some other way manifests energy, 

 that energy is released by the living thing itself. 



We think of things as being alive when they do something. Yet 

 water may turn a wheel and generate electricity which has a force 

 capable of " doing something." Such a force may set off a blast 



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