O-LevelBiologyGenetics & Variation5090/11 · May/June 2012 · Q381 Mark

A person has blood group A. Which statement about his genotype is correct?

AAt least one of his alleles is dominant.

BHe must be heterozygous.

CHe must be homozygous.

DHis alleles are codominant.

✓ Correct answer

A: At least one of his alleles is dominant.

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Topic: Genetics & Variation, O-Level Biology (syllabus 5090). Multiple choice, 1 mark.
Source: O-Level Biology, May/June 2012 Paper 1 Variant 1, question 38.

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