Why might a point mutation in DNA make a difference in the level of a protein's activity?
A) It might result in a chromosomal translocation.
B) It might exchange one stop codon for another stop codon.
C) It might delay the rate of DNA replication.
D) It might substitute a different amino acid in the active site.
E) It might substitute the N-terminus of the polypeptide for the C-terminus.

Question

Quizplus · Accepted Answer

A point mutation that substitutes a different amino acid in the active site of a protein can affect the shape and function of the protein, potentially altering its activity level. This can happen if the substitution leads to a different chemical property or shape of the amino acid, which can disrupt the interactions between the protein and its ligand or substrate, or affect the stability of the protein structure. Choices A, B, C, and E are not relevant to the effect of a point mutation on protein activity levels.

Why Might a Point Mutation in DNA Make a Difference