What are Okazaki fragments?

Okazaki fragments are short segments of DNA that are synthesized during the replication of the lagging strand. The lagging strand is created in a discontinuous manner due to the direction of DNA synthesis, which occurs 5' to 3'. As the replication fork unwinds, this allows for the formation of small fragments, or Okazaki fragments, that are later joined together by DNA ligase to create a continuous strand.

This process is essential because while one strand (the leading strand) can be synthesized continuously in the direction of the replication fork, the other strand must be synthesized in pieces as the fork progresses, hence creating the need for these short segments. Understanding Okazaki fragments is crucial for grasping the complexities of DNA replication and the necessity of both continuous and discontinuous synthesis to maintain the integrity of the genetic material.