358 DIGESTION. 



liquefied, but is not otherwise acted upon. In normal diges- 

 tion, the pancreatic juice does not acidify fats. 



Raw starch which becomes hydrated in the stomach 

 and cooked starch are changed. into sugar by the pancreatic 

 juice, and in this form are absorbed. In this the pancreatic 

 secretion is aided by the intestinal juice, a fluid which pos- 

 sesses the same property, though in a less degree. Cane- 

 sugar and milk-sugar are probably changed into glucose by 

 the pancreatic juice alone. This change takes place to a very 

 slight extent in the stomach. 



The albuminoids, such as gluten, fibrin, albumen, caseine, 

 and musculine, which have been disintegrated but not dis- 

 solved by the gastric juice as they pass out of the stomach, are 

 liquefied by the pancreatic juice with the aid of the bile and 

 the intestinal juice, are changed into albuminose, or peptones, 

 and are thus absorbed. This takes place whether the reac- 

 tion of the contents of the intestine be alkaline, acid, or neu- 

 tral. Though the action of the pancreatic juice, out of the 

 body, soon induces putrefaction in many of the albuminoids, 

 this does not occur in the natural process of digestion. The 

 presence of a small quantity of fat retards this putrefactive 

 change in artificial digestion, and it may have some influence 

 upon the digestion of these principles in the intestine. ' 



As the different articles pass out at the pylorus, in the 

 natural process of digestion, they are in the condition most 

 favorable for the action of the intestinal fluids. The starch 

 is always hydrated, with the particles separated and distrib- 

 uted through the entire mass of food ; the oil is freed from 

 the vesicles in which it is enclosed in the adipose tissue, and 

 is likewise distributed through the alimentary mass ; the ni- 

 trogenized articles are disintegrated, softened, and reduced to 

 a pultaceous mass ; and, in fine, all the food which has not 

 been digested in the stomach is prepared to absorb with 

 avidity the fluids which it meets in the intestine, so that it 

 rapidly undergoes the final changes which take place in this 

 part of the digestive apparatus. Again, the food is passed 



