When allele A is dominant over allele A', write out the parental phenotypes and genotypes. Then write out the offspring phenotypes and genotypes as well as the number of each.
If we were to complete Punnet squares for all of the potential parents' genotypes and phenotypes there are 3 different possible genotypes for children and parents with 2 possible phenotypes for each.
- AA, homozygous dominant
- AA', heterozygous
- A'A', homozygous recessive
- AA & AA', showing dominant allele A
- A'A', showing recessive allele A'
All options for crosses are as follows:
- AAxAA: Both parents hom. dom. with phenotypes showing dominant allele A. This would give 4 hom. dom. children...
(The entire section contains 245 words.)
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