Question

How many amino acids will be translated by the mRNA sequence – 5’CCCUCAUAGUCAUAC3’ if an adenosine residue is inserted after 12th nucleotide?

• A. 2 amino acids
• B. 3 amino acids
• C. 5 amino acids
• D. 6 amino acids

Answer 1

The correct option is A 2 amino acids

$\begin{array}{ccccccc}{5}^{\prime }& \underset{–}{CCC}& \underset{–}{UCA}& \underset{–}{UAG}& UCA& UAC& 3^{\prime }\\ & \downarrow & \downarrow & \downarrow & & & \\ & AA& AA& Stop& & & \\ & & & Codon& & & \end{array}$
So only two amino acids will be formed.