Why Is There a Need for a Specialized Structure at the Ends

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Examlex · Accepted Answer

The Answer is Because all known DNA polymerases elongate DNA in the 5´ to 3´ direction,all require a RNA or DNA primer to initiate synthesis.As the replication fork approaches the end of the chromosome,DNA synthesis on the leading strand continues to the end of the chromosome without a problem.However,because the lagging strand is synthesized discontinuously,it cannot be replicated in its entirety.When the RNA primer is removed,a short segment of DNA remains single-stranded with no way to make this region double-stranded.If there were no specialized mechanism for replicating DNA at the ends,then the chromosome would shorten with each round of replication.Telomerase is the enzyme that completes DNA synthesis at the telomeres.

Why Is There a Need for a Specialized Structure at the Ends

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