DNA Replication Process

00:00 3 marks

3. The diagram shows the process of DNA replication.

[VISUALIZATION: Diagram showing a DNA double helix unwinding at a replication fork. Include labels for Helicase (Enzyme X), DNA polymerase, template strands, and newly synthesized strands (showing one leading and one lagging conceptually).]

(a) Identify the enzyme labelled X, responsible for unwinding the DNA double helix.
[1]
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(b) Outline the role of complementary base pairing in DNA replication.
[2]
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Part a

2 minutes 1 marks

Question

Identify the enzyme labelled X, responsible for unwinding the DNA double helix.
[1]
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Hint Hint

Hint

Look at the diagram where the DNA helix is being ‘unzipped’. What enzyme performs this function?

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Complete Answer

Helicase

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Part b

3 minutes 2 marks

Question

Outline the role of complementary base pairing in DNA replication.
[2]
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Hint Hint

Hint

How does the specific pairing of A with T and G with C contribute to the accuracy of copying DNA?

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Complete Answer

Complementary base pairing ensures that the new DNA strands synthesized during replication are accurate copies of the template strands. Adenine (A) pairs specifically with Thymine (T), and Guanine (G) pairs specifically with Cytosine (C).

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