Study the mRNA segment given below, which is complete and to be translated into a polypeptide chain.
(i) Write the codons ‘A’ and ‘B’
(ii) What do they code for?
(iii) How is peptide bond formed between two amino acids in the ribosome?
(i) A-AUG, B-UAA/UAG/UGA
(ii) AUG codes for methionine UAA/UAG/UGA does not code for any amino acid but, brings about termination of polypeptide, synthesis.
(iii) In the large subunit of ribosome, there are two sites in which subsequent amino acids bind to and come close enough for the formation of peptide bond. It is catalysed by the enzyme called peptidyl transferase.