Chap. 11 



FOODS AND NIHKITION 



Table 11.3 



The Main Actions of Chemical Digestion 



187 



* Trypsinogen is an inactive enzyme produced by the pancreas. It passes into the intestine 

 in the pancreatic juice, is there acted upon by enterokinase produced in the intestinal wall, 

 and becomes the active enzyme trypsin. 



vessel of one dog is connected by a rubber tube with the blood vessel of an- 

 other. After food given the first dog has arrived at the pylorus, the gastric 

 glands of the second dog begin to secrete gastric juice although that dog has 

 been given no food. This shows clearly that they are stimulated by a hormone 

 carried by the blood from one dog to the other. 



The time that food remains in the stomach depends mostly upon its con- 



