Same answer chain

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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

This question is about genetic disorders.

Figure 6 shows the inheritance of a genetic disorder in a family. Person 7 and person 8 plan to have another child. Determine the probability that the child will be a male who has the disorder. You should: • draw a Punnett square diagram • identify the genotype of person 7 and the genotype of person 8 • identify the phenotype of each offspring genotype • use the symbols: H = dominant allele h = recessive allele Probability of having a male child with the disorder =

Figure 6 from the source question paper. — Figure 6

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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.