CHAPTER VI 

 THE LIVER AND PANCREAS 



Section i. 



The Liver. 



In considering the function of the liver it is necessary to bear 

 in mind its peculiar blood supply. Most glands of the body 

 which are called upon to produce a secretion are furnished only 

 with arterial blood for the purpose, but the liver is an exception 

 to this rule ; the entire venous blood returning from the splanchnic 

 area — viz., the bowels, stomach, spleen, pancreas, etc. — consti- 

 tutes the material with which the liver is flooded. Such a mixture 

 of blood derived from a peculiar and considerable area must be 

 charged with many products, some the result of secretory 

 activity, others the soluble constituents of the elements of food ; 

 or, again, substances absorbed from the intestinal canal, which 

 are by-products produced during the gradual breaking-down of 

 the food substances. It is from this blood that the liver performs 

 its various functions, and one of the most evident — viz., the 

 secretion of bile — will be dealt with first. 



Bile. 



The bile is a fluid of an alkaline reaction, bitter taste, a specific 

 gravity in the ox of 1022 to 1025, in the sheep from 1025 to 1031, 

 and in the horse 1005. The colour is yellowish-green or dark 

 green in herbivora, reddish-brown in the pig, and golden-red in 

 carnivora. These differences in colour depend upon the character 

 of the pigment present. Bile taken direct from the liver is rela- 

 tively watery in consistence ; that taken from the gall-bladder 

 is viscid, due to admixture with nucleo-albumin during its stay 

 in the latter receptacle. The secretion contains no protein, 

 which is somewhat remarkable ; biliary pigments, bile acids, 

 fats, soaps, lecithin, cholesterin, and inorganic salts are found in 

 varying quantities. By standing in the gall-bladder the solids 



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