Final answer:
The discovery of Okazaki fragments indicated that DNA synthesis is discontinuous on the lagging strand, which is synthesized away from the replication fork in short segments that are later joined together.
Step-by-step explanation:
The discovery of Okazaki fragments suggests that DNA synthesis is discontinuous. Okazaki fragments are short stretches of DNA on the lagging strand, which is synthesized in the direction away from the replication fork. DNA replication overall is bidirectional, with two replication forks moving away from the origin in opposite directions. However, while one strand (the leading strand) is synthesized continuously in the direction towards the replication fork, the opposite strand (the lagging strand) is synthesized in Okazaki fragments. These fragments are later joined together to create a continuous strand.
It is important to clarify that the Okazaki fragments are a result of the limitation that DNA polymerases can only add nucleotides to the 3' end of the newly forming DNA strand. As the lagging strand template is exposed in the 5' to 3' direction away from the replication fork, it is synthesized in a series of Okazaki fragments, each initiated by a short RNA primer. Each of these fragments is then connected by DNA ligase, rendering the strand eventually continuous.