Final answer:
In nonreplicative transposition, the enzyme transposase cleaves the insertion sequence at the ends of the inverted repeats, allowing the transposon to insert into a new site without excising the original copy.
Step-by-step explanation:
In nonreplicative transposition, the enzyme that specifically cleaves the insertion sequence at the ends of the inverted repeats is known as transposase. During this process, transposase binds to the transposon ends, catalyzing single-stranded cleavage, which leaves staggered ends. This enzymatic activity results in a staggered cut at the target DNA site, allowing for the insertion of the transposon. Following the insertion, DNA repair mechanisms fill in the gaps, and ligation completes the insertion process. This ultimately leaves copies of the transposon at the new site, thereby not removing the original copy but replicating it.