8 exam-style questions. 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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4.31 Random fertilisation and variation
Exam question
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Explain how random fertilisation increases genetic variation.
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Total for this question: 2 marks
4.31 Random fertilisation and variation
Exam question
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Which produces genetic variation in offspring?
(1)Total for this question: 1 mark
4.31 Random fertilisation and variation
Exam question
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Explain why siblings (other than identical twins) look different.
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Total for this question: 2 marks
4.31 Random fertilisation and variation
Exam question
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A person can make about 8 400 000 genetically different gametes from chromosome assortment alone. Calculate the number of different zygotes possible from two parents, in standard form.
(2)Total for this question: 2 marks
4.31 Random fertilisation and variation
Exam question
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Explain why sexual reproduction helps a species survive a change in environment.
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Total for this question: 2 marks
4.31 Random fertilisation and variation
Exam question
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Compare the variation in offspring from sexual and asexual reproduction.
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Total for this question: 2 marks
4.31 Random fertilisation and variation
Exam question
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Suggest one disadvantage of variation from sexual reproduction for a farmer, and explain why it matters.
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Total for this question: 2 marks
4.31 Random fertilisation and variation
Exam question
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State the name of the cell formed when two gametes fuse.
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Total for this question: 1 mark
