76 PRINCIPLES OF PHYSIOLOGY 



(3) Steatolytic or Lipolytic Decompose fats 

 into fatty acids and glycerine. Ex. : Steapsin 

 or Lipase of pancreatic juice. 



(4) Proteolytic Change proteins into pro- 

 teoses, peptones, polypeptides, and at last into 

 amino-acids. Ex. : Pepsin of gastric juice ; 

 trypsin of pancreatic juice. 



(5) Peptolytic Decompose proteoses and 

 peptones into polypeptides and amino-acids. 

 Ex. : Erepsin of intestinal juice. 



(6) Blood ferments Cause clotting of blood. 

 Ex. : Thromhin (fibrin ferment) ; rennin of 

 gastric juice converts caseinogen of milk into 

 casein. 



(7) Ferment of ferments Enzyme that stim- 

 ulates the formation and action of the trypsin 

 of the pancreatic juice. Ex : Enterokinase of 

 duodenum. 



(8) The acid chyme, when it leaves the 

 stomach, leads to the formation of an enzyme, 

 secretin, which is absorbed into the blood and 

 stimulates the secretion of pancreatic juice, 

 Probably other chemical substances act in 

 a similar way, on various secretions. These 

 are called hormones 



