Genetic Code:

During replication and transcription a nucleic acid was copied to form another nucleic acid. Hence these processes are easy to conceptualise on the basis of complementarity. The process of translation requires transfer of genetic information from a polymer of nucleotides to a polymer of amino acids.

The salient features of genetic code are as follows:

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

(ii) Some amino acids code for only one amino acid, hence it is ambiguous and specific.

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

(iv) The code is nearly universal, for example, from bacteria to human UUU would code for phenyl alamine (Phe).

(v) The codon is read in mRNA in a contiguous fashion. There are no punctuations.

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