Which strand of DNA is synthesized continuously?

The leading strand of DNA is synthesized continuously in the direction of the replication fork. During DNA replication, the double helix unwinds, and the leading strand is synthesized in the 5' to 3' direction as the DNA polymerase moves along the template strand. This continuous synthesis occurs because the leading strand is oriented such that its synthesis can proceed without interruption.

In contrast, the lagging strand is synthesized discontinuously in short segments known as Okazaki fragments, which are later joined together. These fragments are necessary because the lagging strand runs opposite to the direction of the replication fork, requiring the polymerase to repeatedly start new segments of synthesis.

The terms "Okazaki strand" and "complementary strand" also do not accurately describe the process as they refer to specific aspects of DNA synthesis or pairing, rather than the nature of continuous or discontinuous synthesis. The leading strand remains the key concept that highlights continuous replication during the DNA synthesis process.