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HUMAN PHYSIOLOGY 



CHAP. VIII 



78. Absorption of Fats. Although fats and oils are 

 acted upon by the pancreatic juice, and by the bile, 

 which together break them up into very small drop- 

 lets surrounded by a thin film of soap, they are never 

 really dissolved as the other foods are. They are still 

 butter, lard, tallow, oils, etc. They are not digested but 

 simply emulsified. In the intestines a small amount of 



FIG. 54. Villi of the small intestine (Zuppke) : A, the lacteal at rest ; B, the 

 lacteal filled up with foods ; C, the muscles contracting and forcing the 

 foods out into the lymphatic vessels. 



soap is formed to aid in the absorption of the fats. 

 Water and oil will not mix. Oil of any kind on the 

 hands is washed off with difficulty without soap. 



Fats and oils are not absorbed with the other foods; 

 they have a route of their own. The mucous membrane 

 of the small intestine has millions of little projections 

 called villi all over its vast surface. A villus is merely 

 a fold of the mucous membrane, in the center of wJiicJi is 



