Vni. DIGESTION (contmued). 



After the action of the mouth the food is ready to be 

 passed on to the stomach, where the next steps in diges- 

 tion take place. The first step in this process is the act 

 known as swallowing or deglutition. In this action the 



Pig. 32 — Swallowing or deglutition ; a, tongue ; b, pharynx ; c, food bolns ; d, soft 

 palate ; e, uvula ; /, epiglottis. 



A shows food being pushed back by the tongue. M shows position of uvula and 

 epiglottis as food falls into the pharynx. 



uvula at the back of the mouth is raised automatically to 

 close the nasal passage, and the tongue simply pushes the 

 food backward until it falls or slips into the pharynx 

 cavity. 



Structure of the pharynx cavity. — (See Fig. 24. ) This 

 cavity is a conical bag just back of the mouth cavity and 

 about five inches in depth. It has seveii apertures ; two 

 into the nasal cavity at the top, two into the ear (the 

 Eustachian tube openings), one into the mouth, one into 

 the windpipe (glottis), and one into the esophagus or 



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