A short segment of an mRNA molecule is shown below. The polypeptide it codes for is also shown: 5' -AUGGUGCUGAAG : methionine -valine -leucine -lysine
Assume that a mutation in the DNA occurs so that the fourth base (counting from the 5' end) of the messenger RNA now reads A rather than G. What sequence of amino acids will the mRNA now code for? (You do not need a copy of the genetic code to answer the question.)

Question

Quizplus · Accepted Answer

The original mRNA sequence is 5'-AUGGUGCUGAAG. If the fourth base changes from G to A, the sequence becomes 5'-AUGAUGCUGAAG, which codes for methionine-methionine-leucine-lysine.

A Short Segment of an MRNA Molecule Is Shown Below