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BIOLOGY FOR BEGINNERS 



and Roux developed the antitoxin for diphtheria. In the United 

 States, deaths from this cause have decreased from 15 to 2 per 

 10,000 of population in fact 98 per cent will recover if treated 

 within two days. In similar ways we are learning to control ty- 

 phoid fever, tetanus, influenza, and pneumonia. Our knowledge 

 of the means of transmission of disease has led to preventive meas- 

 ures even more efficient in preserving human life. 



Another result of modern investigation is the cheering fact that 

 no germ disease is hereditary. You may inherit low resistance to 

 germ attack, but if precautions are taken to increase this resistance 

 and avoid infection, you need not suffer from the disease. 



COMPARISON OF PASTEURIZING AND BOILING MILK 



