Answer:
Plasmids
Step-by-step explanation:
A plasmid is an extra chromosomal DNA. These are small sized double stranded circular DNA. It is generally present in the bacterial cells. Plasmids are present in bacteria and some eukaryotic cells. During bacterial cell division, the plasmid is also copied and moves to the daughter cells. During bacterial conjugation, plasmids get transferred from one bacterium to another bacterium. Plasmids are used as vector by the scientists during manipulation of genes.