THE DIGESTION OF STARCH 49 



3. Name two advantages to the plant of this new 

 process you have studied. 



4. The changing of an insoluble substance to a soluble 

 one and dissolving it is digestion. 



5. Briefly enumerate, in order, using the proper 

 scientific terms, the processes that you have learned 

 take place in a green leaf from sunrise to sunrise 

 again. 



B. Conversion of Starch to Sugar'. 



Experiment 32. To see if starch may be digested 

 to sugar by an enzyme. 



1. Into a test-tube one-half full of a dilute starch 

 mixture place several drops of iodine. 



2. Add to this mixture a few drops of a solution of 

 diastase. 



3. At intervals of fifteen to twenty minutes test for 

 sugar. Describe all color changes observed through- 

 out the experiment. 



C. State with special care and detail the inferences warranted 

 by experiments 31 and 32. 1 



1 NOTE: The study of proteins and fats is here omitted, not being con- 

 sidered essential in an introductory course. 



