Final answer:
The short lengths of DNA produced by the discontinuous replication of the lagging strands are called Okazaki fragments. They are synthesized in short segments away from the replication fork. These fragments are later joined to create a continuous DNA strand.
Step-by-step explanation:
The short length of DNA produced by the discontinuous replication of the lagging strands is called Okazaki fragments. During DNA replication, there are two strands: the leading strand and the lagging strand.
The leading strand is replicated continuously in the direction toward the replication fork. In contrast, the lagging strand is replicated in the opposite direction from the replication fork, in short segments, which are the Okazaki fragments. These fragments are later joined together to form a continuous strand.
Okazaki fragments are synthesized in a direction away from the replication fork because DNA polymerases can only add new nucleotides to the 3' end of a DNA molecule.
Therefore, the synthesis has to occur in a series of segments, starting with an RNA primer, and each new fragment begins closer to the replication fork than the previous one. After these fragments are synthesized, the RNA primers are replaced with DNA, and DNA ligase joins the fragments to form a continuous complementary strand.
The discovery of Okazaki fragments was crucial for understanding how DNA replication works and was a significant contribution to molecular biology. It was discovered by the Japanese research team and married couple Reiji and Tsuneko Okazaki in 1966.
The process on the lagging strand is a more complex than on the leading strand due to the need to repetitively synthesize and join short fragments, but both processes are essential for the accurate replication of DNA.