8 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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4.21B Codominance
Exam question
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Explain what is meant by codominance.
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Total for this question: 2 marks
4.21B Codominance
Exam question
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Which blood group shows codominance?
(1)Total for this question: 1 mark
4.21B Codominance
Exam question
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In some flowers, red (CR CR) and white (CW CW) are codominant. Explain the phenotype of a CR CW plant.
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Total for this question: 3 marks
4.21B Codominance
Exam question
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Give the genotypes of the offspring from a cross between two CR CW plants and give the ratio of phenotypes.
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Total for this question: 2 marks
4.21B Codominance
Exam question
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Explain why a person with blood group O has genotype IO IO.
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Total for this question: 2 marks
4.21B Codominance
Exam question
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Predict the possible blood groups of children of an AB parent and an O parent.
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Total for this question: 2 marks
4.21B Codominance
Exam question
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Explain why codominant inheritance means the genotype can be read from the phenotype.
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Total for this question: 2 marks
4.21B Codominance
Exam question
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State the three alleles for the ABO blood group gene.
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Total for this question: 1 mark
