what happens at the replication fork
Primase synthesizes the RNA primer that is used to start an Okazaki fragment on the lagging strand. DNA polymerase III continues to add nucleotides to the leading strand right at the replication fork. DNA polymerase I (not at the replication fork) replaces the RNA primers with DNA nucleotides. DNA ligase, also not at the replication fork fuses the new nucleotides produced by polymerase I with the adjacent strand. Replication continues until there are two completely seperate DNA strands that are identical.