1 90 Physiology. 



The Work of the Large Intestine. Most of the ab 

 sorption is accomplished in the small intestine ; but as the 

 food passes on into the large intestine the work of digestion 

 and of absorption is carried somewhat farther. If the 

 residue be not soon expelled, there may be absorption of 

 some of the results of putrefactive changes, and a sort 

 of general poisoning of the whole body. Hence the 

 great importance of regularly and thoroughly emptying 

 the lower bowel. The matter thus expelled is largely 

 made up of indigestible material, with some real waste 

 substances. 



Taking up again our comparison of the body and a 

 stove, we see that the feces are not true waste products, 

 but are rather clinkers, or material that has not been 

 burned or oxidized in the body. The real wastes of the 

 body are the carbon dioxid, urea, water, etc., that are pro- 

 duced by the oxidation of the tissues, and are mostly thrown 

 off by the lungs, kidneys, and skin. 



Effect of Alcohol on the Liver. Alcohol is absorbed by 

 the blood capillaries of the mucous membrane of the stom- 

 ach and intestine, and so goes directly to the liver through 

 the portal vein. Alcohol is capable of seriously injuring 

 both the structure and the functions of the liver. 



Alcohol and the Structure of the Liver. We have 

 already learned that the main reason why the liver is so 

 tender and delicate in structure is because it has in it so 

 little connective tissue. Alcohol causes an increased de- 

 velopment of connective tissue in the liver, so that the 

 continued use of alcoholic liquors makes the liver hard and 

 tough. This over-growth of the connective tissue presses 

 upon and squeezes out the soft tissue of the liver cells, so 

 that the surface is covered with little roughened elevations 



