The Various Substances Made by Plants 



Living Protoplasm 



^Enzymes 



Proteins 



Amides 



-Alkaloids 



It may perhaps have occurred to the 

 reader ere this to inquire what proportion 

 of the original basal photosynthate is used in 

 the construction of each of these classes of 

 substances. The question is a fair one but 

 difficult to answer, partly because the pro- 

 portions would be so different with the vari- 

 ous kinds of plants, and partly because we 

 have so few data for making calculations. 

 However, it is possible to make a generaliza- 

 tion for plants as a whole, and this has been 

 done in the table below, which, although lit- 

 tle more than a guess, has yet some value. For simplicity I have 

 reduced the table to the kinds of known and visible substances, 

 grouping together the others as " special substances"; and inci- 

 dentally I have added the ultimate fate of the various groups. 



-Oils-Resins 



Carbohydrates 



I 

 (Photosynthate) 



