146 WHAT IS LIFE 



Peculiarity of the organism. — The life-process 

 is irreversible. Once life has been initiated, the 

 life-process runs on until death. 



3. Peculiarity of the dual-system. — The process that 

 is initiated with the beginning of a dual-system is 

 essentially a process of transformations and trans- 

 mutations. The dual-system appropriates selectively 

 of surrounding material and transforms it into itself. 



Peculiarity of the organism. — The organism 

 synthesizes its own specific material. The growth 

 and maintenance of the organism involves active 

 anabolism. 



4. Peculiarity of the dual-system. — It is the Z-system 

 that organizes the Y-system. 



Peculiarity of the organism. — It is "life" that 

 builds the organism. 



5. Pecidiarity of the dual-system. — The Y-plus 

 system will continue the process of organizing, adding 

 to itself after its peculiar manner, until a limit is 

 reached, the limit set by conditions of equilibrium, 

 when the system will divide. After division, the sepa- 

 rate parts have individual existence; and the pieces 

 severally will continue the process until they in turn 

 have reached the limit permitted by the totality of 

 the factors that are involved. Another division will 

 follow; again the pieces will continue the process; and 

 so on forever. 



