CHAPTER 1 • WHAT DISTINGUISHES LIVING THINGS? 



1 Are tliere animals tliat do not move? 



2 Can plants feel? 



3 Can insects hear? 



4 Are plants alive in the same way as animals are? 



5 What is there the same about plants and animals? 



6 Are animals alive in the same way as we are? 



7 Can plants protect themselves? 



8 What becomes different in a plant or an animal when it dies ? 



9 Can part of a living animal be dead, like a dead branch on a 



tree ? 

 10 Are there parts of animals that are of no use? 



We distinguish various kinds of natural objects by their colors, shapes, 

 sizes, and arrangement of parts. But being aliife is not like being round 

 or soft or purple. It means doing something. Living is acting in a cer- 

 tain way. 



When we speak of a "live spring" or of a "live volcano", we mean that 

 there is action. But we do not confuse a spring or a volcano with living 

 things. A cloud moves across the sky, and it constantly changes its shape; 

 but it is not alive. Action is a necessary part of our idea of life; but action 

 is not sufficient to distinguish the living from the nonliving. 



How do living things differ from other objects? Is it their structure? 

 or their chemical composition ? or the particular things they do ? or the way 

 they originate ? Are plants alive in the same way as we are ? What is there 

 about living things that makes them alive, that keeps them alive? 



How Are Plants and Animals Alike? 



The Parts of Plants^ If we examine a geranium plant, or any other 

 small plant that is easily handled, we find that the part below ground (the 

 root) differs in several ways from the part above ground (the shoot). They 

 differ in color and in texture. The smallest branches or subdivisions of the 

 root are, as a rule, more delicate than those of the shoot. In most kinds of 

 plants the shoot consists of distinct stem and leaves, which differ from each 

 other in shape, color, and texture. 



At certain seasons of the year the stem bears other structures besides 

 leaves, namely flowers. Most kinds of flowers last but a short time and are 

 succeeded by fruits, inside of which there are usually seeds. And these parts, 

 the seeds, as we already know, are the beginnings of new plants. 



iSee No. 1, p. 27. 

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