Question

the allele for attached earlobe is recessive. In the third generation, what are the odds that a carrier father and homozygous dominant mother will have ta child with an attached earlobe?

Answer 1

0% chance because the mother carries only the dominant gene because she is homologous

Answer 2

Earlobes are either free or attached in humans and this trait is inherited but its inheritance pattern is not easy to predict. The earlobe trait is determined by a single gene. Free earlobe is a dominant over attached earlobe. When a carrier father married to homozygous dominant mother then 50 % progeny will be with free earlobe and 50 % will be carrier for free lobe.