Okazaki fragments play a crucial role in the replication of the lagging strand during DNA replication.

These fragments are short sequences of DNA nucleotides, measuring approximately $100$ to $200$ base pairs in length for eukaryotes and up to $1000$ base pairs in prokaryotes. They are synthesized discontinuously and subsequently linked together by the enzyme DNA ligase to form the lagging strand during DNA replication. The discovery of these fragments in $1968$ by Reiji and Tsuneko Okazaki led to their naming in their honor.

DNA replication is a complex process that begins with the unwinding of the double helix structure of the DNA molecule, a task performed by the enzyme DNA helicase. Once the DNA is unwound, another enzyme called DNA polymerase synthesizes a new strand of DNA using the original strand as a template. However, DNA polymerase can only add nucleotides in the $5'$ to $3'$ direction. As a result, while one strand, known as the leading strand, can be synthesized continuously, the opposite strand, referred to as the lagging strand, must be synthesized in smaller fragments known as Okazaki fragments.

The synthesis of Okazaki fragments starts with the enzyme RNA primase, which creates a short RNA primer. This primer serves as a starting point for DNA polymerase. Following this, DNA polymerase adds DNA nucleotides to the primer, thus forming an Okazaki fragment. After an Okazaki fragment has been synthesized, the RNA primer is removed by another enzyme, DNA polymerase I, which replaces it with DNA nucleotides. Finally, the gaps between the Okazaki fragments are sealed by DNA ligase, resulting in a continuous DNA strand.

The discovery and understanding of Okazaki fragments have been pivotal in elucidating the process of DNA replication. Without these fragments, the replication of the lagging strand would be impossible, potentially compromising the integrity of genetic information. Thus, Okazaki fragments are essential for maintaining the accuracy of DNA replication and ensuring the correct transmission of genetic information from one generation to the next.