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Genetics and heredity — Question 3

QCAA 2023, Paper 2 · 7 marks

Q3 · 2023 · Paper 2Unclassified7 marks

QUESTION 3 (7 marks)

The chart shows the inheritance pattern of a trait, which is thought to be sex-linked dominant.

| nd 1 2

omene 3 4 5 6 7

eeeuenes 8 9 10 11 12 #13 ~ «14

Biology question figure

a) Identify how many offspring of individuals 1 and 2 have the trait.

b) Identify evidence to support the conclusion that the trait is sex-linked dominant. Justify your response using a Punnett square. [4 marks]

c) Infer the genotype of individual 6. Explain your reasoning. [2 marks]

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