Correct option is A
Correct Answer: (a)
Explanation: Terminal inverted repeats (TIRs) are integral components of most DNA transposable elements. They flank the transposon and are recognized by the transposase enzyme during movement. The sequences that are generated during insertion are target site duplications, not terminal inverted repeats. Therefore, the statement claiming that repeats are not part of the transposable element is incorrect.
Information Booster
· Terminal inverted repeats are short, identical sequences present at both ends of a transposon.
· They serve as recognition and binding sites for the transposase enzyme.
· TIRs move together with the transposable element during transposition.
· A functional transposase and intact terminal inverted repeats are sufficient for transposition.
· TIRs are characteristic of DNA transposons but absent in many retrotransposons.
Additional Knowledge
During transposon insertion, duplication of a short stretch of host DNA occurs at the target site, forming target site duplications that flank the inserted element. These duplications are host-derived sequences and are distinct from terminal inverted repeats, which are inherent parts of the transposable element itself. Confusing target site duplications with terminal inverted repeats is a common conceptual error in questions related to transposition mechanisms.
