Final answer:
Topoisomerase relieves the pressure that results from separation of DNA strands by breaking and reforming DNA's phosphate backbone ahead of the replication fork.
Step-by-step explanation:
Topoisomerase is an enzyme involved in DNA replication. It relieves the pressure that results from separation of DNA strands by breaking and reforming DNA's phosphate backbone ahead of the replication fork, thereby preventing DNA breakage. This prevents the DNA from becoming overwound and tangled.