Origins of DNA Replication - Assignment Example

In eukaryotes such as humans, chromosomes exist as large complexes of nucleotides that are tightly bound to histones. DNA replication proceeds in two directions (bi-directionally) and is semi-conservative (“DNA Replication” 1). Parent DNA strands act as a template to the formation of new daughter strands complementary to each other. DNA replication occurs in the synthesis stage of the cell cycle (Devlin 234). Infrequently dividing cells, DNA replication should occur rapidly to supply new copies of DNA at the end of mitosis in the cell cycle.

Since the DNA in eukaryotes are long and consists of thousands of base-pairs, starting in only one origin takes too much time. Thus, it is necessary that there would be several ori sequences starting simultaneously to speed up the replication process. Each time the cell divides, the ori sequences ensure that the replication starts and terminates efficiently (DePamphilis 47). At the end of each replication, the fragments will then be joined together with special enzymes to form each of the elongated DNA molecules.