* DNA polymerase: This enzyme is responsible for adding new nucleotides to the growing DNA strand, using the existing strand as a template. It also has a proofreading function to ensure accuracy in replication.

* Helicase: This enzyme unwinds the DNA double helix, separating the two strands so that each can be used as a template for replication.

These two proteins work together to ensure that DNA is accurately copied during replication.