Page 2 



Group III 



11. (a) Name two diseases the germs of which may be transmitted through 



infected milk or water. 

 (b) Explain fully the method of prevention for one of these diseases. w^ 



12. (a) Mention the principal organisms which may render each of the following 



foods unfit for human use: grain, milk, fruit, meat. 

 (b) Explain the principles involved in the preservation of food by drying, by 

 canning, by refrigerating, and by salting. 



13. Describe the structure, growth, and reproduction, and the means of distribu- 



tion of the bread mold. 



14. (a) What is the probable cause of influenza ? 



(b) How is the infection transmitted ? 



(c) What precautions have scientific value ? 



(d) WTiat popular precautions are useless ? 



(e) What should a person with the influenza do (1) for himself ? (2) for the 



community ? 



15. Mention the principal organisms, living in a field, which are of service to 



the growing crops and explain why each is beneficial. ,^ 



«P 



