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Read a Simplified Single-Gene Cross - Practice 2

These fictional traits follow one autosomal locus with two alleles, equal gamete probabilities, and complete dominance of A.

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These fictional traits follow one autosomal locus with two alleles, equal gamete probabilities, and complete dominance of A. Use the supplied parents to calculate a probability for each offspring. Real traits can follow more complex inheritance.

Worked example

Aa x Aa gives AA, Aa, Aa, aa in equally likely combinations. The aa probability is 1/4, not a promise that exactly one of four offspring has aa.

A Punnett square for Aa x Aa has column gametes A and a and row gametes A and a. Its four cells are AA, Aa, Aa and aa, giving aa probability one quarter under the stated model.
A Punnett square for Aa x Aa has column gametes A and a and row gametes A and a. Its four cells are AA, Aa, Aa and aa, giving aa probability one quarter under the stated model.
Question 1 Fictional single-gene model: Aa x Aa. With equal gamete probabilities, what percentage probability does one offspring have of genotype AA? Enter the number without %.
Question 2 Fictional single-gene model: AA x aa. With equal gamete probabilities, what percentage probability does one offspring have of genotype AA? Enter the number without %.
Question 3 Fictional single-gene model: Aa x aa. With equal gamete probabilities, what percentage probability does one offspring have of genotype Aa? Enter the number without %.
Question 4 Fictional single-gene model: AA x Aa. With equal gamete probabilities, what percentage probability does one offspring have of genotype aa? Enter the number without %.
Question 5 Fictional single-gene model: Aa x Aa. With equal gamete probabilities, what percentage probability does one offspring have of genotype Aa? Enter the number without %.