A YEAR IN SCIENCE 



113 



Shake the tubes and set them aside in a temperature 

 of 36 C. for 24 hours. 



At the end of that time examine : 



No. 1 for starch and sugar. 



No. 2 for starch and sugar. 



No. 3. Has the egg-white dissolved? 



No. 4. Has the olive oil changed? 



Upon which foodstuffs does pancreatin act? Does it 

 act in an acid or base solution? From the last three 

 exercises complete the following table : 



Exercise 76. Absorption. 



Object: To determine which foodstuffs will diffuse 

 through an animal membrane. 



Corn starch 

 Olive oil 

 Egg-white (raw) 

 Iodine 

 Ammonia 

 Nitric acid 



Apparatus 



Thistle tube 

 Animal membrane 

 Glass jar 

 Ring stand 

 Twine 



Directions: For the method of setting up the 

 apparatus for this exercise, see Exercise 5 on "Diffu- 

 sion of Liquids through a Membrane. ' ' Set up similar 

 experiments, using in place of the molasses : 



