RESPIRATION 



205 



TRACHEA . 



LARYNX 



LUNGS . 



EXPIRATION 



Bronchi . . 



Bronchial 

 tubes 



f Two rings . 

 [ Contains . 



INSPIRATION 



TOPICAL OUTLINE 



f Cartilaginous rings. 

 Structure . . . -j Fibrous tissue. 



[ Lined with ciliated epithelium. 

 f C-shaped. 



Rings -i Complete in front. Incomplete behind. 



[ Connected by fibrous tissue. 

 ( Right and left. 



/ In structure similar to trachea. 

 Rings of cartilage very imperfect. 

 Cartilage disappears in smallest tubes, 

 which terminate in groups of air-cells. 



Complete behind. 

 Cricoid cartilage A complete ring. 

 Vocal cords. 

 Epiglottis Closes the glottis. 



(Right Three lobes. 

 Left Two lobes. 

 f Air-vessels Bronchial tubes and cells. 

 Vessels . . . . J f Pulmonary arteries. 



[ Blood-vessels -j Capillaries. 



[ Pulmonary veins. 



( External intercostals contract. 



Raise the ribs. 



r Chest enlarged j Make the chest wider. 

 I Diaphragm depressed. 

 I Chest made deeper. 

 Lungs expand with the chest. 



Air rushes in through the trachea, filling the enlarged lungs. 

 ( Elastic walls of the thorax recoil. 

 Elastic lungs recoil. 

 Internal intercostals con- 

 tract. 



Ribs depressed. 

 Chest becomes narrower. 

 Diaphragm raised. 



Chest made shallower. 

 Abdominal muscles contract. 

 Abdominal organs press on 



under side of diaphragm, j 

 Air forced out through the trachea. 



r Chest made 

 smaller 



Forced 

 expiration. 



