Question

A section of dna has the sequence: 5'agcgttaccgt3'. if, as a result of mutation, this sequence changed to: 5'aggcgttaccgt3', what sort of change would this represent?

a. a nonsensical mutation
b. a point mutation
c. a missense mutation
d. a frameshift mutation
e. a silent mutation

Answer 1

D. Frameshift mutation. (All downstream codons are affected)

Answer 2

The change in the DNA sequence represents a b. point mutation, which could be silent, missense, or nonsense, depending on the effect on the amino acid sequence.

Step-by-step explanation:

The change from 5'AGCGTTACCGT3' to 5'AGGCGTTACCGT'3 is an example of a b. point mutation, which in this case is a substitution of a single base pair.

There are different types of point mutations, including silent mutations, missense mutations, and nonsense mutations.

A silent mutation does not change the amino acid sequence of a protein because the new codon still codes for the same amino acid.

A missense mutation results in the substitution of a different amino acid, which can affect the protein's function.

A nonsense mutation introduces a stop codon, which terminates the protein synthesis prematurely, potentially leading to a non-functional protein.

In this particular case, without information about the resulting amino acids, we cannot determine whether this change is silent, missense, or nonsense.

However, if this substitution does not change the encoded amino acid, it would be a silent mutation. If it alters the amino acid, it would be a missense mutation.

If it results in a stop codon, it would be a nonsense mutation. Frameshift mutations, which include insertions and deletions that shift the reading frame, are not indicated by this singular base pair change.