A mRNA sequence that codes for a protein is 5′-CAA GGG UAC-3′.Which of the following choices does NOT cause a change in the amino acid sequence?
A) 5′-CAA GCG GUA C-3′
B) 5′-CAG GGG UAC-3′
C) 5′-GAA GGG UAC-3′
D) 5′-CAA GGG UAA-3′
E) These are all mutations.

Question

Quizplus · Accepted Answer

Choice B (5′-CAG GGG UAC-3′) does not cause a change in the amino acid sequence because it represents a synonymous mutation, where the codon is changed but it still codes for the same amino acid due to the redundancy in the genetic code.

A MRNA Sequence That Codes for a Protein Is 5′-CAA