Why might a point mutation in dna make a difference in the level of a protein's activity? why might a point mutation in dna make a difference in the level of a protein's activity? it might delay the rate of dna replication. it might exchange one stop codon for another stop codon. it might substitute a different amino acid in the active site. it might substitute the n-terminus of the polypeptide for the c-terminus. it might result in a chromosomal translocation?