Same answer chain

Use this to connect the question's starting point to the final result.

Use parent genotypes to identify possible gametes

Combine gametes to derive offspring genotypes

Map each offspring genotype to the affected or unaffected phenotype

State a probability that matches the derived offspring outcomes

Current question

AKU is a genetic disorder. Figure 3 shows the inheritance of AKU in one family.

A female who has AKU and a male who is heterozygous for AKU plan to have a child. Determine the probability that the child will have AKU. You should: • complete Figure 4 • identify the phenotype of each offspring genotype • use the symbols: A = dominant allele a = recessive allele.

Figure 4 from the source question paper. — Figure 4

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Why this earns marks

1 Use parent genotypes to identify possible gametes.
2 Combine gametes to derive offspring genotypes.
3 Map each offspring genotype to the affected or unaffected phenotype.
4 State a probability that matches the derived offspring outcomes.

Common weak answer: Names the topic but skips the middle reasoning links.