68 VITALISM AND SCHOLASTICISM 



substances of diametrically opposite character, 

 they being more complicated in their nature 

 and less stable. During this " anabolic " pro- 

 cess energy is absorbed. 



And on the other hand there is the reverse 

 process called " catabolic," in which these un- 

 stable, complex substances are broken up into 

 simpler and more stable matters, a process 

 accompanied by the giving out of energy. 

 Further one must remember that the chemical 

 processes which take place in a cell may be 

 looked at, from quite another point of view, as 

 dual. There are the processes which are car- 

 ried on for the renewal of the cell itself and for 

 the maintenance of the various energies of 

 which it is the seat, and this is true whether 

 the cell is isolated a unicellular organism or 

 whether it is one of many as a portion of a 

 multicellular organism. But, secondly, in many 

 cases other substances, which we may speak of 

 as bye-products, are constructed in the course 

 of the operations carried on in the cell-labora- 

 tory. These bye-products do not appear to be 

 of primarily or indeed of any importance to 

 the cell, and may be actually injurious to it 

 if retained, yet they are or may be highly bene- 

 ficial or even necessary to other parts of the 

 body, or in other cases they may be of high 

 value to other living creatures, wholly uncon- 



