Question

Which amino acid is coded for by the mRNA codon UAA a) start codon b) stop codon c) Leu d) Asn

Answer 1

It is a Stop Codon, so B. Your answer is B.

Answer 2

The correct answer is a) stop codon.

Codons in an mRNA are encoded during translation process of protein synthesis. It begins with a start codon on mRNA and goes till a stop codon is reached. The Codons UAG, UGA and UAA on the mRNA do not encode any amino acids because they are called nonsense or stop codons. A nonsense codon causes end of polypeptide synthesis.