Question

Which one of the following is a wrong statement regarding mutation?

• A. Deletion and insertion of one or two base pairs cause frame-shift mutation
• B. Cancer cells commonly show chromosomal aberrations
• C. UV and gamma rays are mutagens
• D. Change in a single base pair of DNA does not cause mutation

Answer 1

The correct option is D Change in a single base pair of DNA does not cause mutation

Any changes in DNA sequence is referred to as mutation. Mutation in single nucleotide base of a DNA segment is called as a point mutation. It can introduce a premature stop codon or a nonsense codon in the transcribed mRNA or changes a codon specifying a different amino acid.

Insertion or deletion of one or two bases changes the reading frame from the point of insertion or deletion. Such mutations are referred to as frameshift mutations.

Cancer cells commonly show chromosomal aberrations.

UV rays and γ-rays (gamma rays) are mutagens, i.e., the mutation causing agents.

Hence, option d is the wrong one.