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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4.27 Sex determination
Exam question
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Draw a genetic diagram to show the inheritance of sex in humans.
(3)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 3 marks
4.27 Sex determination
Exam question
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Use a genetic diagram to calculate the probability, as a percentage, that a baby is a boy.
(2)Total for this question: 2 marks
4.27 Sex determination
Exam question
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Explain why a family with three girls has the same chance of a boy next time.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
4.27 Sex determination
Exam question
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What are the sex chromosomes of a zygote that will develop into a girl?
(1)Total for this question: 1 mark
4.27 Sex determination
Exam question
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Explain why the ratio of boys to girls born is close to 1 : 1.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
4.27 Sex determination
Exam question
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Suggest why a small family may have all boys.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
4.27 Sex determination
Exam question
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Calculate the probability that a couple's first two children are both girls.
(2)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 2 marks
4.27 Sex determination
Exam question
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State the sex chromosome present in every egg.
(1)Write your answer, then press Show model answer and tick each mark point your answer makes. Your answer is not saved.
Total for this question: 1 mark
