144 ABSORPTION 



place when the peptone passes through the mucous cells; that 

 there a certain per cent of the proteid is split off as a sugar. If 

 that is the case, it is cA-ident that this sugar may be transformed 

 in the liver to glyccigen, and hence proteid is to a certain extent a 

 glycogen former. Some evidence seems to indicate that fat may 

 also be changed to glycogen, but tliis has' not been satisfactorily 

 proved at the present time. 



Glycogen is formed in the muscles and in other parts of the 

 body than the liver. In all these cases, it is made from the grape 

 sugar in the blood and acts as a local supply of reserve energy. 

 The great storehouse, however, is the liver. 



Poisons. — In the intestines are found many forms of bacteria. 

 These in turn may bring about fermentation of the food, and in 

 this way are produced certain injurious substances or poisons 

 which may be absorbed with the digested nutrients. In that 

 case they are brought in the blood of the portal vein to the liver, 

 and one of the important functions of this organ is to destroy 

 these poisons or return them to the intestine with the bile. If, 

 however, any interruption of the bile making of the liver occurs, 

 it loses its power to destroy and give off these poisons, and the 

 result is that they pass into the tissue-supply blood, and poison 

 the body. The results of the entry of these poisons into the 

 system usually manifest themselves in a coated tongue, loss of 

 appetite, headache, and dullness, and such a condition is called 

 biliousness. Certain drugs have the power to stimulate the liver 

 cells and cause a great outpouring of bile which carries with it 

 the poisons, and thus restores the liver to its normal action and 

 sometimes removes the source of trouble. 



Defaecation. — The removal of the faeces from the large 

 intestine results not only in the removal from the body of 

 indigestible material, but also has a vital connection with 

 the poison removing power of the liver. When the bile 

 formed in the liver is poured into the intestine by the gall 

 duct it carries with it the poisons which the liver cells have 

 separated from the blood of the portal vein. If these poi- 

 sons are allowed to remain in the small intestine they will 



