So this purple section is the primer. Our DNA polymerase bind onto our primer and it moves along this fashion, along this direction in a continuous fashion, adding the nucleotide continuously piece by piece in the forward direction in the same direction as the movement of this DNA helicase. But to synthesize the other strand known as the lagging strand, primates creates many RNA primers as far as possible down our parent strand that runs in the five to three direction. And then DNA polymerase works backwards with respect to direction of the movement of this replication fork. So the replication fork moves this way, this is synthesized this way, but this is synthesized in the opposite direction. And we see that the DNA helicase basically reads the parent strand in the allowed three to five direction and it forms the lagging strand in the five to three direction.