Describe semi-conservative DNA replication

The double helix structure unzips which is catalysed by the DNA Helicase enzyme. DNA Helicase overcomes hydrogen bonding between nitrogenous bases. Two strands are produced, each one acts a template. Free DNA nucleotides align with exposed bases following complementary base pairing rules. DNA Polymerase catalyses the joining of adjacent nucleotides to from the sugar-phosphate backbone of the new DNA strand. Hydrogen bonds then form between the bases on each strand and the strands twist to form a double helix. 3 hydrogen bonds form between guanine (G) and cytosine (C), and 2 hydrogen bonds form between adenine (A) and thymine (T). Two identical DNA molecules are produced. Each of the new molecules contains a single strand from the original DNA molecule and a single new strand. Would amount to 6 marks. Each sentence in the first paragraph is a mark.

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Answered by Prashant A. Biology tutor

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