THE RESPIRATORY SYSTEM. . 163 
2. What waste gas is formed in every part of the body exercised? 
3. Through what three channels do waste materials pass from the 
blood? 
4. Describe the manner in which the oxygen of the air reaches the 
blood. 
5. Write a description of the pharynx. 
6. Bisect the larynx in the sagittal plane, make a drawing of the cut 
aspect, and label all features. 
7. How many cartilaginous rings in the trachea and what is their 
use? 
8. Describe as much of the pleura as can be seen in your specimen. 
9g. Do the right and left bronchi have the same number of main 
branches? 
10. Why do the air cells seldom become clogged? 
11. What muscles are largely used in respiration? 
12. Describe the hyoid bone as seen from your dissection. 
13. What part of this bone can you feel beneath your mandible? 
14. How does the carbon dioxid given off by the cells in the foot 
reach the lungs? 
15. What causes the air to enter the lungs? 
16. Inflate the lungs of a freshly killed animal by forcing air from 
your lungs into a glass tube tied into its trachea. 
17. After retaining a full inspiration of air as long as possible, expire 
it through a glass tube into the bottom of a two-liter bottle and insert 
into the bottle a lighted splinter. 
18. Describe the pulmonary circulation 
