INCOME OF MATTER 99 



free acid immediately unites with alkalies in 

 the bowel, potash and soda, to form highly 

 soluble soaps. The pancreatic juice also con- 

 tains a milk-curdling ferment. The action on 

 proteins is to split up the protein molecule into 

 simpler soluble substances, such as leucin, 

 tyrosin, and simpler bodies known as amino- 

 acids. Some of the bodies so formed may be 

 absorbed into the blood, while any excess 

 is probably voided in the faeces. 



51. The whole length of the small intestine 

 contains numerous glands, those in the duo- 

 denum termed the glands of Brunner, while 

 the others are known as Lieberkuhn's glands. 

 These glands secrete the intestinal juice, 

 which has a feeble action somewhat resem- 

 bling that of the pancreas. It contains a 

 special enzyme, erepsin. (See p. 76.) There 

 is also present an enzyme called invertase, 

 which splits up cane sugar into dextrose and 

 levulose. 



52. The great intestine, which is much 

 shorter and wider than the small, may be 

 regarded as a receptacle for the refuse 

 materials of food stuffs that have not been 



