DIGESTION IN SMALL INTESTINE 



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portant functions, two of which are related to digestion. 

 It serves as a storehouse for the excess sugar found in the 

 blood coming from the intestine during digestion, and as 

 a factory for the making of bile. The bile is a thin 

 yellow-green alkaline liquid, which is secreted continu- 

 ously and is stored in the gall-bladder when digestion 



Esophagus 



Pancreatic duct 



FIG. 73. Stomach, beginning of email intestine, and entrance of bile and pan- 

 creatic duct. (Hough and Sedgwick.) 



is not going on. When the acid chyme enters the in- 

 testine, it causes a reflex contraction of the gall-bladder, 

 which thereupon pours out bile through its duct. Un- 

 like the saliva, the gastric juice, and the intestinal juice, 

 bile has no specific action upon starches, sugars, or pro- 

 teids. It is of great use, however, in the digestion and 

 absorption of fat. 



Pancreas. The other of the ducts opening into the 

 small intestine comes from a long gland, the pancreas, 

 which lies at the lower edge of the stomach and along 

 a portion of the intestine. The same stimulation by 

 the acid chyme which causes the gall-bladder to con- 

 tract and force out the bile, also causes the cells of 



