CONCLUSION 



We have learned that the very basis of 

 biological order, of specificity and diversity, is a sequence of a few 

 small molecules. We have learned that nuckic acid, considered on 

 the time scale of the organism, is the stable, permanent structure 

 responsible for the specificity and for the reproduction of specificity. 

 But, considered on the time scale of the world, nucleic acid is the 

 varvintT structure responsible for mutations and evolution. 



Stability and variability reside in the same structure. This dual 

 function of the genetic material is one of the important aspects of 

 hfe. 



Nucleic acid is the blueprint for the synthesis of specific proteins, 

 which in turn are the catalysts for the synthesis of essential 

 metabolites. Nucleic acids and enzymes are, from a functional point 

 of view, complementary macromolecules in the sense that one 

 cannot be produced ^^'ithout the other. 



The organism, or the cell, is a complex molecular society in which 

 macromolecules and groups of macromolecules are interacting. The 

 functioning of each enzyme or group of enzymes, so as their syn- 

 thesis, is controlled by the product of their activity, or better by the 

 needs of the organism. Each group possesses its own regulatory 

 system. All the groups and all the various regulating systems in- 

 teract. 



As a result of evolution, an elaborate system of a feedback mech- 

 anism has developed. The functioning of the organism reflects the 



[99] 



