CHAPTER XLIV 

 BIOLOGY AND HEALTH 



Vocabulary 



Excessive, more than necessary. 

 Mastication, chewing. 

 Flexible, easily bent. 

 Vagaries, whims. 



One of the chief reasons for the study of biology is to learn how 

 to properly care for our own body and to maintain both it and its 

 surroundings in healthful condition. 



The science which deals with the care and health of the body is 

 called hygiene; that which deals with keeping its environment 

 healthful is called sanitation. 



A great many foolish " rules of hygiene " have been devised but 

 if we will apply our general knowledge of biology, mixed with a 

 goodly amount of common sense (which is not common), we can 

 construct our own. We know the amount and kinds of foods re- 

 quired, and can judge the evils of improper or excessive eating. 

 We know the need and process of digestion and can reach our own 

 conclusion as to chewing food, care of teeth, removal of waste, etc. 



We have learned the use of oxidation and can see the reason for 

 correct posture, clothing, and exercise, which affect breathing. 

 In this way a sensible human being ought to be able to apply bi- 

 ology to his own life and it is much better than trying to memorize 

 any set of rules, however wise they may be. 



In the same way, sanitation means the knowledge of biology 

 as applied to food and water supply, infectious diseases, ventila- 

 tion, sewerage, clean streets, etc. 



In our elementary work we have studied both these subjects to 

 some extent. This chapter will. merely attempt to summarize a 

 few of the principal facts. 



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