Explain the process of semi-conservative DNA replication.
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The enzyme DNA helicase breaks the hydrogen bonds between the two polynucloetide DNA strands causing the double helix to unzip, forming two single strands.
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Each original single strand then acts as a template for a new strand. Free-floating DNA nucloetides join to the exposed bases on each original template strand via complementary base pairing.
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The nucloetides of the new strands are joined together by the enzyme DNA polymerase. This forms the sugar-phosphate backbone. Hydrogen bonds form between the bases on the original and new strand and the strands twist to reform the double helix.
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Each new DNA molecule contains one strand from the original DNA molecule and one new strand, hence the term semi-conservative replication.
BJ
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