DNA REPLICATION - polymerase. 5. DNA polymerase removes the...

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DNA REPLICATION DNA polymerase can add new nucleotides only to the 3' end, or in the 5'   3' direction.  Keeping this in mind, here are the steps in DNA replication: 1. Enzyme unwinds the double strand and proteins stabilize the unwound DNA. 2. A replication fork forms at a fixed site called the origin of replication. 3. One new strand, the leading strand, is synthesized continuously by DNA polymerase.  Available nucleotides from the cytoplasm are linked. 4. The other new strand, the lagging strand, is synthesized in little bits at a time. For each little  section, RNA polymerase synthesizes a short RNA primer, which is extended by DNA 
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Unformatted text preview: polymerase. 5. DNA polymerase removes the RNA primer and replaces it with DNA. 6. DNA ligase joins the bits of the lagging strand. In some bacteria, two replication forks form and move in opposite directions around the chromosome until they meet. DNA polymerase evaluates the new strand as it forms, checking that the new base is really complementary to the base of the parent strand. If an incorrect base sneaks in, the enzyme will snip it out and replace it. This is to ensure that very few mistakes are made in the copying process....
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This note was uploaded on 01/23/2012 for the course MCB MCB2010 taught by Professor Smith during the Fall '09 term at Broward College.

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