ANATOMY OF THE RESPIRATORY ORGANS 



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The Larynx. This lies in front of the esophagus, its upper 

 opening communicating with the middle pharynx. It is com- 

 posed of four cartilages and the muscles and ligaments which 

 hold them together. The cartilages keep its lumen constantly 

 open, while the muscles effect movements concerned in degluti- 



FIG. 47. Diagram of the respiratory organs. 



The windpipe leading down from the larynx is seen to branch into two large 

 bronchi, which subdivide after they enter their respective lungs. (Yeo.) 



tion, respiration and phonation. The cartilages are the thyroid, 

 cricoid and two arytenoids. The two alae of the thyroid meet at 

 an acute angle in front to form the Adam's apple. The cricoid 

 is at the lower end of the larynx, completely surrounding 

 it. The arytenoids are movable and rest upon the back of the 

 cricoid. (Fig. 48.) 



The vocal cords, two ligamentous bands covered by a thin 

 layer of mucous membrane, stretch antero-posteriorly across 

 the upper end of the larynx, while the false vocal cords, having 

 nothing to do with phonation, and pinker in color, are above 



