21 exam-style questions · Biology only (B): not in Science (Double Award). Write your answer, check it against the mark scheme and tick the points you earned. Your marks stay on this device. Your writing is not saved.
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4.16B DNA structure
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Describe the structure of DNA.
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Total for this question: 4 marks
4.16B DNA structure
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Which base pairs with adenine in DNA?
(1)Total for this question: 1 mark
4.16B DNA structure
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State the complementary base pairs in DNA.
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Total for this question: 2 marks
4.16B DNA structure
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Give the complementary strand for the DNA sequence ATGCCTA.
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Total for this question: 1 mark
4.16B DNA structure
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A DNA sample contains 30 % adenine. Calculate the percentage of guanine.
(2)Total for this question: 2 marks
4.16B DNA structure
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A DNA molecule contains 18 % cytosine. Calculate the percentage of adenine.
(2)Total for this question: 2 marks
4.16B DNA structure
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Explain why the base pairing in DNA is called complementary.
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Total for this question: 2 marks
4.16B DNA structure
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Name the three parts of a nucleotide.
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Total for this question: 3 marks
4.16B DNA structure
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Explain why the sequence of bases is important.
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Total for this question: 2 marks
4.16B DNA structure
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Describe how DNA can be extracted from strawberries.
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Total for this question: 3 marks
4.16B DNA structure
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Explain why washing-up liquid is used in DNA extraction.
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Total for this question: 2 marks
4.16B DNA structure
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Explain why ice-cold ethanol is used in DNA extraction.
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Total for this question: 2 marks
4.16B DNA structure
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Suggest why strawberries yield a lot of DNA.
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Total for this question: 2 marks
4.16B DNA structure
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What holds the two DNA strands together?
(1)Total for this question: 1 mark
4.16B DNA structure
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Explain why hydrogen bonds between strands being weak is useful.
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Total for this question: 2 marks
