t t T t One parent is homozygous, recessive (tt) for PTC tasting and cannot taste the substance; the other parent is heterozygous (Tt) with a dominant allele for PTC tasting and can taste it. List Genotypes (two alleles): Genotypes: Phenotypes: ____ % % ____ % % ____ % % ____ % % A S A S Both parents are heterozygous (AS) with one dominant allele for normal red blood cells and one allele for sickle cell anemia. List Genotypes (two alleles): Genotypes: Phenotypes: ____ % % ____ % % ____ % % ____ % % .