Final answer:
Okazaki fragments are short DNA sequences on the lagging strand, which are synthesized away from the replication fork and later joined to form a continuous strand. They initiate with an RNA primer and are named after the researchers who discovered them in 1966. DNA ligase connects these fragments to create an unbroken DNA strand.
Step-by-step explanation:
Understanding Okazaki Fragments in DNA Replication
Okazaki fragments are crucial to understanding how DNA replication occurs on the lagging strand. Unlike the leading strand which is synthesized continuously, the lagging strand is replicated in short sections in the direction away from the replication fork. These short sections are known as Okazaki fragments, each beginning with an RNA primer that must later be replaced with DNA nucleotides. The process involves an enzyme called DNA ligase, which helps to connect the Okazaki fragments, thus sealing the nicks and forming a continuous DNA strand.
The discovery of Okazaki fragments was significant, attributed to Reiji and Tsuneko Okazaki after their research in 1966. These fragmented DNA stretches are formed due to the antiparallel nature of the two DNA strands, meaning DNA polymerase can only add nucleotides in a 5' to 3' direction. Consequently, the discontinuous synthesis of the lagging strand results in the formation of Okazaki fragments that are later linked to form a single, unbroken DNA strand.