(2) Replication must not be confused with duplication. In duplication, a copy
of the original is made and the original remains intact. In replication, the original divides
and forms two new molecules that resemble the original. Figure 4-13 shows a DNA
molecule in replication, before or during mitosis, cell division. The weak hydrogen bond
between the nitrogen bases is released and the DNA molecule starts to split. Each
separation leaves an exposed nitrogen base that will recombine with nitrogen bases
found in the cytoplasm of the cell. When they recombine, the second molecule will be
identical to the original molecule, as seen in figure 4-14.
Figure 4-13. Deoxyribonuciel molecule in replication.
Figure 4-14. Two DNA molecules resulting from replication.