DNA unwinds and unzips at the origin of replication
Helicase breaks the hydrogen bonds between base pairs
Single-strand binding proteins keep the strands apart
Topoisomerase relieves twisting ahead of the replication fork
Primase adds short RNA primers
DNA polymerase adds complementary nucleotides in the 5′ to 3′ direction
The leading strand is synthesized continuously
The lagging strand is synthesized in fragments called Okazaki fragments
RNA primers are removed and replaced with DNA
DNA ligase joins the DNA fragments together
Two identical DNA molecules are formed, each with one original strand and one new strand