1 86 BIOLOGY AND HUMAN LIFE 



9. What work is done by the right chambers of the heart ? by the 

 left? 



10. What changes take place in the blood while it is passing through 

 the capillaries of the intestines ? of the lungs ? of the muscles of 

 the arm ? 



11. How does the blood in the pulmonary veins differ from the blood 

 in veins leading from the brain ? 



12. How does the blood in the pulmonary arteries differ from the blood 

 in the pulmonary veins ? in muscular veins ? 



13. How does the blood in the arteries going to the brain differ from 

 that in the veins leading from the brain ? 



14. How is the work of the heart carried on in a tree ? 



REFERENCE READINGS 



Bergen and Caldwell. Practical Botany, pp. 78-80. 

 OsTERHOUT, W. J. V. Experiments with Plants, pp. 224-258. 

 BiGELOW^, M. A. Applied Biology, pp. 53-55, 482-486. 

 Hough and Sedgw^ick. The Human Mechanism, pp. 13 5-1 51. 

 Parker, George H. Biology and Social Problems, lecture on Hormones. 

 Public Health Reprint 896, Importance of our Knowledge of Thyroid 

 Physiology. 





