Question

select the correct answer. which mutation does the given change in nucleotide sequence represent? attgcatc → atacgttc a. translocation b. substitution c. inversion d. duplication

Explanation:

• Substitution: A substitution mutation is when one nucleotide is replaced by another. In the given change \(ATTGCATC

ightarrow ATACGTTC\), we can see that specific nucleotides are being replaced. For example, the \(T\) at position 3 (\(ATTGCATC\)) is replaced by \(A\) (\(ATACGTTC\)) and the \(G\) at position 4 (\(ATTGCATC\)) is replaced by \(G\) (no change here), but looking at the overall sequence, there are nucleotide - by - nucleotide replacements.

• Translocation: Translocation involves the movement of a segment of DNA from one location to another (either within the same chromosome or to a different chromosome). This is not the case here as we are not seeing a segment shift.
• Inversion: Inversion is when a segment of DNA is reversed end - to - end. The given sequence change does not show a reversal of a segment.
• Duplication: Duplication is when a segment of DNA is copied. There is no indication of extra copies of DNA segments in the given change.

Answer:

B. substitution