Question

The schematic representation given below shows a DNA strand and two types of mutations in the DNA strand.

(i) Identify the type of mutation exhibited in I and II. 

(ii) Which of the above mutation is more harmful? Give reason.

Answer 1

(i) I is point mutation; II is Frame shift

(ii) II as more codons are affected;

It is extremely likely to lead to large-scale changes to polypeptide length and chemical composition/ resulting in a non-functional protein that often disrupts the biochemical processes of a cell/Incorrect amino acids are inserted/ often premature termination occurs when a nonsense codon is read/ Frameshifts have very severe phenotypic effects.