THE HEREDITARY ORDER: GENETIC INFORMATION 



only one — let us say A — possesses the right sequence of triplets 

 suitable for the coding of amino acids and the synthesis of pro- 

 teins. The other — let us say B — would be able to produce only 

 a complementary RNA strand A. It could also be that a temporary 

 RNA double helix is formed, or that the single-stranded RNA pro- 

 duces a double-stranded DNA. The mechanism would be the re- 

 verse of the synthesis of RNA from DNA. Anyhow, the problem 

 is not solved — not yet solved. Let us, for the time being, forget the 

 question of the replication of the ribonucleic acid and of viruses 

 containing ribonucleic acid. 



Conclusions 



The conclusion has been reached that each organism contains a 

 structure, desoxyribonucleic acid, which is the very base of heredi- 

 tary order. This structure contains the information for the pro- 

 duction of specific templates and of specific proteins. Because DNA 

 is composed of two complementary strands, its reproduction is the 

 production by each of the strands of a complementary one. The 

 specificity of nucleic acid is the sequence of the nucleic bases, and 

 the specificity of proteins is the sequence of the amino acids. A 

 change in the base sequence results in a change in the nucleic acid 

 specificity. 



"If it be true," wrote Max Delbriick in 1949, "that the essence 

 of life is the accumulation of experience through the generations, 

 then, one may perhaps suspect that the key problem of biology, 

 from the physicist's point of view, is how living matter manages 

 to record and perpetrate experience." The key problem is now 

 solved. 



REFERENCES 



Anfinsen, C. B. (1959). The Molecular Basis of Evolution. John Wiley & Sons, 

 New York. 



Baldwin, E. (1947). Dyna77nc Aspects of Bioche772istry. The University Press, 

 Cambridge. 



Dunn, L. C., ed. (1951). Genetics in the 20th Century. The Macmillan Com- 

 pany, New York. 



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