Replication forks

Definition

A replication fork is the area where the DNA double helix is unwound to allow for replication of each strand. It forms a Y-shape and is crucial for the synthesis of new DNA strands.

5 Must Know Facts For Your Next Test

1. Replication forks are formed at the origins of replication.
2. DNA helicase is the enzyme responsible for unwinding the DNA at the replication fork.
3. At each replication fork, there are leading and lagging strands that are synthesized in opposite directions.
4. Single-strand binding proteins stabilize the unwound DNA strands at the replication fork.
5. DNA polymerase adds nucleotides to the growing DNA strand at the replication fork.

Review Questions

• What enzyme unwinds the DNA at a replication fork?
• Explain the difference between leading and lagging strands at a replication fork.
• Why are single-strand binding proteins important at a replication fork?

Related terms

DNA Helicase: An enzyme that unwinds the DNA double helix during DNA replication.

Leading Strand: The continuously synthesized strand of DNA created in the direction of the replication fork.

Lagging Strand: The discontinuously synthesized strand of DNA created away from the direction of the replication fork in short fragments called Okazaki fragments.