292 IV. THE PRINCIPLES OF LIFE PHENOMENA 



will be readjusted by the gene during mitosis, but it seems possible 

 that part of the protoplasm or the proteins may be deformed too far 

 to be repaired ; such proteins must be expelled from the cell. This 

 may be the other reason for the rapid exchange of the protein, which 

 is known especilly manifest in tissues of active function. 



The infection with viruses generally results in the nucleic acid 

 increase in the cell as referred to already. Similar increase appears 

 to be brought about by proper chemical or physical stimuli, followed 

 by the active synthesis of proteins. It is considered that an adequate 

 stimulus applied to protoplasm may enable the protein to acquire an 

 active state leading to the temporary liberation of polar groups, as 

 may occur in general in the protein denaturation ; as a result capacity 

 of combining with nucleic acids or the function of synthesizing nucleic 

 acids may be enhanced. The enhancement in the action of phospha- 

 tase is apparently associated with the increase in the amount of 

 nucleic acids (112), suggesting that in the active state of protoplasm 

 the polar groups acting as phosphatase are also liberated. Phospha- 

 tase activity thus enhanced may be favourable for the liberation of 

 energy. 



As mentioned previously, it seems necessary to hold constant in 

 the protoplasm the amount ratio of nucleic acid to protein for the 

 smooth establishment of life processes. If so, the increase in the 

 protein amount will follow the increase in nucleic acid content in. 

 order to maintain the ratio contant. There is ample evidence that 

 nucleic acid accumulation does occur before protein synthesis (29). In 

 short, the increase in the amount of nucleic acid, which may be 

 caused by the temporary liberation of polar groups in protplasm pro- 

 teins following a stimulus, may lead to the enhancement of the 

 template effect resulting in the active synthesis of protein, whereby 

 the constant ratio of nucleic acid to protein is recovered, and thus the 

 cells or the organism may be able to hold the state favourable for the 

 continuance of their existence. 



There seems no doubt that the constant ratio of nucleic acids to 

 proteins is indispensable for organism. Therefore the mechanism to- 

 keep the ratio as constant as possible should be highly developed in. 

 organisms ; and those failed to obtain the mechanism would surely 

 become extinct. 



There appears no particular reason why mainly RNA is increased 

 on the application of certain stimuli which may activate the protoplasm 

 structure, but for the rapid synthesis of protein which alleviates the 

 unbalance in the ratio of nucleic acid to protein, RNA must be more 

 adequate than DNA. Thus the accumulation of RNA would be 

 favourable for the organisms if the organisms were brought under 



