Question

A frame shift mutation

a. can lead to a longer protein

b. can lead to a shorter protein

c. does not change the resulting protein

d. changes the way codons are read by the ribosomes

e. changes the way codons are read by the ribosomes and can lead to a longer or shorter protein

Answer 1

The correct option is E.

Frameshift mutations induce insertion or deletion of nucleotides in the DNA. This causes a shift in the reading frame of the string of triplet codons on the mRNA. Deletion or addition of nucleotides may cause abnormal amino acids to be incorporated during translation. This is because of the disturbed reading frame in which codons change due to insertion or deletion of nucleotides. Several additions can cause the strand to lengthen and produce a longer polypeptide chain. Several deletions can cause the strand to shorten and produce a shorter polypeptide chain. Few insertions or deletions may also lead to the formation of stop codon in between the strand, causing the abnormal ending of polypeptide chain synthesis.

Option A and B cannot be correct because option E includes an important point i.e. change in the reading frame.

Option C cannot be correct because frameshift mutations do cause a change in the resulting protein.

Option D cannot be correct because option E harbors the point of lengthening and shortening of the proteins as well.