124 



DIGESTION 



The internal structure shows it to be composed of a mass 

 of many sided bodies called lobules. Each lobule (see 

 Fig. 44) consists of a mass of cells (hepatic ceUs) sur- 

 rounded by a network of capillaries. Branches of the bile 

 ducts also enter these lobules and receive the bile which 

 the hepatic cells secrete from the blood. Each hepatic 

 cell, therefore, is a trije gland cell, and the combined secre- 

 tion of all these cells is collected in the branched ducts 

 and flows downward until it enters the common hepatic 

 duct. From this point it may take one of two courses. 



.-s^;;^'^'**^- 





Fig. 45 — The pancreas ; 1, central duct ; 2, pancreatic duct ; 3, stomach. 



It either enters the common bile duct and flows directly 

 into the intestine or it backs up and accumulates in the 

 gall bladder. In this way bile is stored in this bladder 

 so that when necessary it may be called on to supply the 

 intestine with increased amounts of bile. In such case, 

 bile flows from the lobes of the liver and from the gall 

 bladder directly into the intestine. The bile is a thick 

 golden-brown liquid of bitter taste. About a quart is 

 produced daily, and performs very important functions in 

 digestion. 

 The pancreas.— (See Fig. 45 and Ex. XXXII.) This 



