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LIFE PROCESSES OF MAN 



pancreas, comes into contact with the digested and partly 

 digested food, causing three different changes. One is to 

 complete the change of proteins into simpler products ; a 

 second is to finish converting starches into sugar ; while 

 the third is to assist the bile (the digestive juice made in 

 the liver) to digest the fats. The digestion of the food is 

 practically completed in these three regions of the diges- 

 tive tube, although digestion continues to some extent 

 after the food is passed into the large intestine. 



The pepsin in the gastric juice is called an enzyme 

 (C'li'zim: Greek enzymos, fermented) or ferment. There 

 are three different enzymes in the pancreatic juice, none 

 in the bile, and one in the saliva. These enzymes are the 

 chemical bodies which digest food. All plants and animals 

 digest their food by means of enzymes. 



Inorganic foods, such as water, oxygen, and salts, man 

 takes into his body, making them part of his living pro- 

 toplasm, or using them in oxidation. There is a large 

 amount of water in man, enough to make up nearly two- 

 thirds the total weight of his body. AH of his food con- 

 tains water. 

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STUDENT REPORT 

 Where the Food is Digested 



Teacher may explain yeast and bean to help out the comparison. 



