QUESTIONS 



1 In what different ways is the total amount of Hfe at any given time or place 

 limited by the physical environment? 



2 What conditions bring about an increase in the numbers of any species of 

 plant or animal, including man? a decrease in numbers? 



3 In what ways are the numbers of individuals of one species in a given region 

 limited by other species? 



4 How can we show that the activity of one pari of the body depends upon that 

 of another? or that it may interfere with the full activity of another part? 



5 \\'hat advantages come to a living thing through the division of labor among 

 organs and tissues? What disadvantages? 



6 What are the conditions for a high degree of division of labor among human 

 beings? among different nations? 



7 What usually happens to a natural community when man arrives on the 

 scene ? 



8 To what extent can man control the numbers of other living things in any 

 given region? the numbers of his own racei^ 



9 How are post-war conditions likely to influence the distribution of popu- 

 lations? 



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