Q. State the number of amino acids produced by the given mRNA sequence when the 16th base is substituted by uracil.
5' A U G C G C A A A C C C U A G C G A 3'

 178  161 NTA AbhyasNTA Abhyas 2020 Report Error

Solution:

Stop codons are sequences of three nucleotides that signal the termination of polypeptide synthesis during the translation process. These are also called nonsense or termination codons.
The three RNA stop codon sequences are UAG, UAA and UGA and they do not code for an amino acid.
In the given sequence, four amino acids will be incorporated in a polypeptide chain because the 5th codon will become UGA (stop codon) after substitution of C with U.