Answer:
DNA replication requires a very high energy. It has to be fast and accurate as well. Therefore instead of opening in one go, long DNA molecules of eukaryotes have a large number of replicons all of which work simultaneously.
Step-by-step explanation:
While replicating, the entria DNA molecule to keep the whole molecule stabilised does not open in one go because it would be highly expens energetically. ... Actually , unwinding creates tension in the molecule us cucoiled parts start forming super coils due to the interaction of exposed nucleotides