Final answer:
Primase function varies between the leading and lagging strands during DNA replication, with continuous synthesis on the leading strand and fragmented synthesis via Okazaki fragments on the lagging strand, each requiring a new primer.
Step-by-step explanation:
The frequency of primase function on the two strands of DNA during replication is indeed dramatically different. On the leading strand, DNA is synthesized continuously, requiring only a single RNA primer at the beginning. In contrast, on the lagging strand, DNA synthesis occurs in short stretches known as Okazaki fragments, with each fragment necessitating a new RNA primer synthesized by primase.
Helicase unwinds the DNA double helix, and single-stranded binding proteins stabilize the unwound DNA. DNA polymerase III extends the DNA from the RNA primers. As replication progresses, the RNA primers on the lagging strand are removed by the exonuclease activity of DNA polymerase I, and the Okazaki fragments are joined by DNA ligase.
Since DNA polymerase can add nucleotides only in a 5' to 3' direction and the strands are antiparallel, one strand (the leading) can be synthesized in the same direction as the replication fork moves, while the other (the lagging) is synthesized in the opposite direction, necessitating the fragmented Okazaki fragments. This process is facilitated by multiple proteins, including primase and the sliding clamp, to ensure both strands are replicated concurrently despite their opposing directions.