The use of some things, such as opium, tobacco, beer, wine, and whisky, creates an unnatural appetite. That is, after one has used these articles a few months he cannot stop their use without great suffering. The younger the person, the sooner the appetite becomes fixed. For this reason young persons should never use tobacco or alcoholic drinks of any kind.
PRACTICAL QUESTIONS
1. What is digestion?
2. Name the parts of the food tube.
3. Where does saliva come from?
4. Explain how the food is acted on in the mouth.
5. Why should food be well chewed?
6. What forms the gastric juice?
7. Of what use is the gastric juice?
8. How long does food stay in the stomach?
9. Name some foods easily digested.
10. What does the intestine do?
11. What are villi?
12. Tell how the food gets into the blood.
13. Of what use is the liver?
14. Why should we not eat too much?
15. Should we eat between meals?
16. Give three reasons why you should not use tobacco.
CHAPTER VIII
THE CARE OF THE MOUTH
Sickness often begins in the Mouth.—A clean mouth and sound teeth have much to do in keeping one well. The germs which cause nearly a half million deaths in the United States every year enter the body through the mouth. If the mouth is unclean, only one or two disease germs entering it may remain there and grow.
