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The salient features of genetic code


The salient features of genetic code

(i)The codon is triplet. 61 codons code for amino acids and 3 codons donot code for any amino acids, hence they function as stop codons.

(ii)One codon codes for only one amino acid, hence, it is unambiguous and specific

(iii)Some amino acids are coded by more than one codon, hencethe code is.
degenerate

(iv)The codon is read in mRNA in a contiguous fashion. There areno punctuations.

(v)The code is nearly universal:for example, from bacteria to human UUU would code for Phenylalanine (phe). Some exceptions to thisrule have been found in mitochondrial codons, and in someprotozoans.

(vi)AUG has dual functions. It codes for Methionine (met) , and it also act as
initiator codon

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