1. How long can an animal live without eating? 2. How long can an animal live without breathing? 3. Why is your body like a sponge? 4. What are cells? 5. How do they get their food? 6. How many kinds of waste come from the body cells? 7. How is each kind carried away from the body? 8. What does the blood carry from the lungs to the body cells? 9. Why does it not carry air? 10. What process keeps your body warm? 11. What happens if the body cannot get oxygen? 12. How are the human lungs formed? 13. What is the windpipe? What are the bronchi? 14. Draw a picture of the lung-tree showing how the tubes branch. 15. What is at the end of each tiny branch? 16. How do the windpipe and the esophagus differ in form? 17. Why is the windpipe stiff? 18. In what four ways is the air you breathe out different from that which you took in? 19. Why does lime-water become milky when you breathe into it? 20. When you run, why do you breathe more quickly? Why does your heart beat faster? 21. How can you improve your "wind"? 22. In fever, why do you breathe more rapidly? 23. How do the ribs and muscles help in breathing? CHAPTER XIV 1. Why is "caged air" dangerous? 2. How is outdoor air kept clean and pure? 3. What is air made of? 4. In what ways do people poison the air? 5. How do plants help to clean the air? 6. What is the best way to ventilate a room? Why? 7. Why do you have recess? 8. How does impure air make children look and feel? 9. Why is an open fire not the best means of heating and ventilating? 10. See if the room you are now in is properly ventilated. Why, or why not? 11. What are disease germs? 12. Why is dusty air unwholesome? 13. What is the safest way to clean a room? 14. Name three groups of disease germs that float in the air. 15. Name three ways in which you can protect yourself against these germs. 16. What is a cold? 17. What is the best way to cure a cold? 18. How can you prevent colds? 19. What causes consumption (tuberculosis of the lungs)? 20. Does the tubercle bacillus attack other parts of the body? 21. Why should a consumptive hold a cloth before his face when coughing? 22. Why should his sputum be burned? 23. Why should he go to a camp or sanatorium? Give two reasons. 24. About how much money could this country afford to spend in fighting consumption? Why? 25. Why need we no longer dread it as people did twenty-five years ago? 26. What methods are used in curing the disease? 27. What methods are used for preventing it? 28. Give two reasons why spitting should be prohibited. 29. What will fresh-air and sunlight do to the disease germs in the dust? 30. What do we know about the germs of pneumonia? 31. Do those who use alcohol stand a good chance in fighting pneumonia? 32. How may pneumonia be prevented? CHAPTER XV