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| Mechanism of DNA Replication |
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| It is a complex process and involves the participation of over a dozen enzymes and other protein factors. |
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| The intertwined DNA starts separating from a particular point and this is known as the origin of replication. |
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| The second step is that the two strands of DNA separate, before each serves as a template for the synthesis of a new strand. |
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| The enzymes helicases unwinds the helix and the enzymes called Topoisomerases break and reseal one strand of DNA. |
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| A primer or a short stretch of RNA formed on the DNA template is formed with the help of the enzyme Primase. |
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| The enzyme DNA polymerase plays an important role in adding the building blocks to the primer in a sequence as influenced by the template. |
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| The double stranded DNA unwinds upto a point, to give rise to Y shaped structure referred to as the Replication fork. |
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| New strands will grow from the fork and as replication proceeds it will appear as if the point of divergence at the fork is moving. |
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| The DNA polymerase can polymerise the nucleotides only in the 5 3 direction. Since the two strands of the DNA are in antiparallel orientation, the two new strands have to be formed by the growth taking place in opposite directions. |
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