But this is not seen. The action of the telomerase enzymes ensure that the ends of the lagging strands are replicated correctly. A well-studied system involves the Tetrahymena protozoa organism. A hairpin occurs when unusual base pairs between guanine residues in the repeat form. Next the RNA primer is removed, and the 5' end of the lagging strand can be used for DNA synthesis.
Ligation occurs between the finished lagging strand and the hairpin.
Thus the end of the chromosome is faithfully replicated. The following figure shows these steps. If the DNA is rapidly cooled, the DNA remains single-stranded. But if the DNA is allowed to cool slowly, sequences that are complementary will find each other and eventually base pair again. Below is a curve that is obtained from a simple genome.