ENERGY IN BIOLOGY. Ill 



verified by experiment We are at liberty to 

 assert either that the protoplasm increases by 

 functional activity or that it is destroyed. Neither 

 the arguments nor the objections pro or con have any 

 decisive value. The facts alleged on either side are 

 capable of too many interpretations. 1 



The only favourable argument (not demonstrative) 

 is furnished by energetics. It is this. The re-building 

 of the protoplasm is not like the organization of reserve- 

 stuff^ a slightly complicated or even simplified pheno- 

 menon, as happens in the case of the reserve of 

 muscular glycogen. The glycogen, in fact, is built up 

 at the expense of foods chemically more complex. 

 It is, on the contrary, a clearly synthetic pheno- 

 menon, certainly of chemical complexity, since it ends 

 in building up the active protoplasm which is, in some 

 measure, of the highest scale of complexity. Its for- 

 mation at the expense of the simplest alimentary 

 materials requires, therefore, an appreciable quantity 

 of energy. 



The assimilation which organizes the active proto- 

 plasm therefore requires energy for its realization. 

 Now, at the moment of functional activity, and by a 

 necessary consequence thereof, the chemical destruc- 



1 The reason is to be found in the large number of indeter- 

 minates in the problem we have to solve. It will be sufficient 

 to enumerate them : the two substances which exist in the 

 anatomical element, protoplasm and reserve-stuff, to which 

 are attributed contrary roles ; the two conditions attributable 

 to the protoplasm, of manifested or latent activity ; the faculty 

 possessed by both of being prolonged for an indeterminate 

 period, and of encroaching each on its protagonist when its 

 existence is at stake. Here are more elements than are neces- 

 sary to explain the positive or negative results of all the 

 experiments in the world. 



