$4 APPLIED PHYSIOLOGY 



the capillaries instead of around the bile tubes. Each cell 

 makes bile from the blood and pours it into its bile tube, 

 down which it runs, uniting with streams from other tubes. 

 All the tubes finally unite their streams in the single bile 

 tube which leads to the intestine. A side tube leads from 

 the large bile tube to a bladder on the under side of the 

 liver, called the gall bladder, which stores the bile when it 

 is not needed in the intestine. 



113. Bile. Bile is a thick, golden-colored liquid of a 

 very bitter taste. It consists of waste albuminous matter, 

 coloring substances, and mineral matters dissolved in water. 

 Although it is a waste product, it has very important uses 

 in digestion. About a quart is produced daily. 



114. Intestinal fluids. As the food enters the intestine 

 it finds three new substances ready to act upon it. These 

 substances are the intestinal juice, the pancreatic juice, and 

 the bile. All these liquids are alkaline, and tend to neu- 

 tralize the acid in the food as fast as it comes from the 

 stomach. 



115. Intestinal juice. The intestinal juice is small in 

 amount, arid contains ferments which change starch to 

 glucose, and albumin to peptone ; but its action is slight, 

 and the amount digested by it is small. 



116. Pancreatic juice. The pancreatic juice is a liquid 

 of which five per cent is made of three ferments which 

 perform the main part of digestion. As the chyme comes 

 from the stomach, it contains albumin, some already di- 

 gested, but much only softened and broken up. It also 

 contains fat and starch unchanged. 



One of the ferments of the pancreatic juice, trypsin, 

 acts upon the undigested albumin, changing it to pep- 

 tone. 



Another ferment, amylopsin, changes the starch and 



