CHAPTER VI 

 THE DIGESTION OF FOOD 



/ 147. How Waste is made good by Food. As we have 

 learned in a previous chapter, our bodies are subject to 

 continual waste, which occurs in no one part alone, but in 

 all the tissues. 



Now the liquid part of the blood comes into direct 

 contact with every one of these tissues, the ultimate cells 

 of which are constantly being bathed by this nutritive fluid, 

 which brings to them the material needed for their renewal. 

 These cells are able to select from the fluid of the blood 

 whatever they require to repair their waste and to provide 

 for their renewed activity. 



To keep the blood from becoming impoverished the 

 materials which it is constantly losing must be supplied 

 from some source outside of the body. This necessitates 

 the ingest ion of articles which are known as food. 



The most important and complicated process by which 

 food is made ready to pass into the blood is known as 

 digestion, and the organs concerned in bringing about this 

 marvelous change in the food are the digestive organs. 

 f 148, The Digestive Organs in General. The digestive 

 apparatus of the human body consists of the alimentary 

 canal and tributary organs which, although outside of this 

 canal, communicate with it by ducts. 



The alimentary canal consists of the mouth, the pharynx, 

 the oesophagus, the stomach, and the intestines. 



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