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http://www.youtube.com/watch?v=AJNoTmWsE0s
端粒形成(Telomere) (lagging strand)
端粒酶　(Telomerase)

ps:
In the end, the lagging strand (which is longer) forms a T-loop, showing that the chromosome is finished. This serves as a protection against losing information, prevents chromosomes to bind to each other and so on. The thing to remember is that telomerase is very often inactive on somatic cells, which means that those chromosomes shorten every time they replicate. This is why we die of age. Cancer cells and stem cells have active telomerase (which is why cancer just keeps on growing).