56 



A. G. PASSYNSKY 



surface layer consisted of 8 molecular layers of RNA, i.e. of those where 

 scores of damages can arise in various places attenuating the total effect 

 of the permeability increase which is undoubtedly of a statistical 

 character. In a mono- or bimolecular layer each damage must consider- 

 ably change the permeability of the layer ; therefore it can be expected 



(J 



a. 





30 



20 



10 



20,000 40,000 60,000 



D 

 Fig. 5 



that the effect discussed can take place in mono- and bimolecular layers 

 directly wdthin the limits of biologically important doses. When 

 obtaining enzyme-substrate systems with finer molecular separating 

 layers of different nature, a considerable lowering of the threshold of 

 the action observed can be expected. 



At any rate, from the viewpoint presented, which was developed in 

 detail earlier (Passynsky, 1957b), it is evident that the key, specific 

 importance of certain damage to molecules in the cell can be explained 

 not by some unique peculiarities of their structure but by their j)artici- 

 pation in molecular interphases. In the light of the theory of open 

 systems the damage of a few molecules in cell interi^hases can lead to a 

 considerable change in the constants of transfer and in the destruction 

 of the organization of biochemical processes in the cell even in those 

 cases when the bulk of enzyme and substrate molecules remain intact 

 (for example, in the action of sublethal doses of radiation). It should be 

 noted that similar conclusions were drawn in our laboratory from the 

 study of enzymic oxidative processes in living objects, in leaves of 

 various plants (Budnitskaya et al., 1956; Passynsky and Vyrovetz, 

 1959). The source of biological strengthening of the action of radiation 

 can thus reside in the sjjecificity of the fine intracellular structure. 



It seems that this factor may play an important part in the mechan- 

 ism of biological strengthening of the action of radiation and. tlierefore, 

 in the theory of the biological action of radiation. 



