Question

In 125 amino acid sequence, if the codon for 25${}_{t}h$ amino acid is mutated to UAA, then

• A. A polypeptide of 124 amino acids is formed
• B. A polypeptide of 25 amino acids is formed
• C. A polypeptide of 24 amino acids is formed
• D. No polypeptides are formed

Answer 1

Answer: (C)

A polypeptide of 24 amino acids is formed

In 125 amino acid sequence if the codon for 25th amino acid is mutated to UAA, then the process of translation will terminate as UAA is a stop codon which cannot be translated by t-RNA. So, the translation of 125 amino acid sequence will terminate at 24 amino acid.

So, the correct answer is option C.