Q12 of 50 Page 1

(i) Name the scientist who suggested that the genetic code should be made of a combination of three nucleotides.

(ii) Explain the basis on which he arrived at this conclusion.


(i) George Gamow suggested that the genetic code should be made up of a combination of three nucleotides.


(ii) He proposed that-


• If 20 amino acids are to be coded by 4 bases, then the codon should be made up of three nucleotides.


43=64


• And if it code by two nucleotides, then it would be less than 20, which is not possible.


42=16


• So the codon was proposed to be triplet.


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