Identify bases in the bottom strand that can be transcribed into start and stop codons. write the mrna sequence (in the form of triplets, for example, ggg-aaa-ccc) that would be transcribed between start and stop codons if the bottom strand served as the template for rna polymerase.

Silent mutations can occur because of the redundancy of the genetic code. For example, the codons CCG and CCU are both translated from mRNA as proline (Pro). So a change in the template strand of the DNA from 3′-GGC to 3′-GGA (a mutation from C to A) will not cause any change in amino acid sequence.

Frame-shift mutations result from the insertion or deletion of one or as valine (Val).

Nonsense mutations result in a premature stop codon. For example, the codon UGG is translated as the amino acid tryptophan (Trp). A DNA point mutation could convert this to the stop codon UAG, which acts as a translation termination signal.