Question

15. A science student claims that a substitution mutation is less likely to affect gene function than an insertion or deletion mutation. Use logical reasoning and evaluate this claim.

Answer 1

Answer: The change in the structure of the genes or change in the DNA sequence is called mutation. The mutations are of different types that are deletion, rearrangement, insertion and others.

Explanation:

Mutation in which the one to several nucleotides get changed at a point is called point mutation. The point mutation can be in the form of deletion, substitution, and insertion. Deletion will involve the removal of nucleotide that involves the change in the sequence of DNA. When the nucleotide is added to the genome it is called insertion. In deletion and insertion the whole sequence of nucleotides from the point of mutation get displaced this affect the codons in the amino acid sequence which is responsible for protein synthesis so the functioning of the body may get affected by such mutations.

In the case of substitution the new nucleotides are added to the DNA sequence and the one which was already present at that place is removed. So, only one amino acid in the sequence will change so the polypeptide structure will not be affected.