what is leading and lagging strand in DNA replication

Answer 1

In DNA replication, the leading strand and the lagging strand refer to the two strands of DNA that are synthesized during the process.

The leading strand is the strand that is synthesized continuously in the 5' to 3' direction, which is the same direction as the replication fork is moving. This means that the DNA polymerase can synthesize the leading strand continuously by adding new nucleotides to the growing DNA strand.

On the other hand, the lagging strand is synthesized discontinuously in the opposite direction of the replication fork, from 3' to 5'. As a result, the DNA polymerase has to synthesize this strand in small fragments called Okazaki fragments. These fragments are later joined together by an enzyme called DNA ligase to form a continuous strand.

Overall, the leading strand is synthesized continuously, while the lagging strand is synthesized in fragments. This is due to the nature of DNA replication, as only one strand can be synthesized in the same direction as the replication fork movement.