204 Physiology. 



17. Diseased kidneys may remove valuable nourishing materials 

 from the blood. 



1 8. The body keeps changing, taking new matter to replace worn- 

 out tissue. 



19. Nutrition includes digestion, absorption, circulation, respiration, 

 assimilation, oxidation, and excretion. 



20. We cannot destroy matter. Our waste products become part 

 of earth or air. 



21. We cannot create force. We get our energy from food as an 

 engine gets its energy from fuel. 



22. We depend on plants for our food. 



23. Alcohol interferes with nutrition at every step. 



Questions. i . Should a person who has studied hard try to do hard 

 muscular work the same day ? 



2. What are the advantages of a " course " dinner? 



3. Which is more wholesome, dry toast or soaked toast ? Why? 



4. Why do we give a horse exercise and keep fattening stock quiet? 



5. Are fat people large eaters ? Are thin people light eaters? 



6. Do sweat glands ever excrete valuable material? 



7. In Fig. 87 find what the blood gives to each organ and what it 

 takes from each. 



8. Classify the organs represented in Fig. 87. 



9. Name the organs that change most rapidly. 

 10. Name the organs that change most slowly. 



n. What is the source from which plants get their energy? 

 12. Is matter defiled in passing from one body to another? 



