The DNA replication process is generally referred to as discontinuous, because the polymerizing enzyme can add nucleotides only in the 5’-3’ direction, synthesis in one strand(leading strand is continuous in the 5’-3’ direction towards the fork. In the other strand (lagging strand), as the forks opens, multiple sites of initiation are exposed. The synthesis, then proceed in short segments in the 5’-3’ direction: that is, synthesis in the lagging strand is discontinuous. The short segments of DNA synthesized on the lagging strand are called Okazaki fragment. These fragments are about 1000 – 2000 nucleotide long.
| No | Leading strand | Lagging strand |
| 1 | It is a replicated strand of DNA which grows continuously without any gap | Lagging strand is replicated strand of DNA which is formed in short segments called okazaki fragments. Its growth is discontinuous |
| 2 | It does not require DNA ligase | DNA ligase is required for joining Okazaki fragments |
| 3 | The Direction of growth of the leading strand is 5’-3’ | The Direction of growth of the lagging strand is 3’-5’ through in each Okazaki fragment it is 5’-3’ |
| 4 | Only a single RNA primer is required | Starting of each Okazaki fragment requires a new RNA primer |
| 5 | Formation of leading strand is quite rapid | Formation of lagging strand is slower |
| 6 | Its template open in 3’-5’ direction | Its template open in 5’-3’ direction |
| 7 | Formation of leading strand begins immediately at the beginning of replication. | Formation of lagging strand begins a bit later than that of leading strand |