1. In humans, the ability to sing well is dominant over the recessive trait of being a terrible

singer. Likewise, the trait to be able to dance is dominant to not being able to dance.

Baby Sean, a Taylor Swift and Joe Alwyn product, was born, Mom is heterozygous for the

ability to sing and she cannot dance. Dad cannot sing, but he can dance (he is

homozygous for the dancing gene), What are the chances that little Sean will be able to

dance and sing?

The probability of Sean to both sing and dance well is 50%.

Explanation:

The gene that is dominant is expressed in phenotype of the individual and the genes are actually obtained from the parents.

Here two characters are mentioned which are singing and dancing.

The dominant character i. e able to sing is marked by gene S and the corresponding recessive allele is marked by gene s.

Similarly, the ability to dance is marked by gene D and recessive allele is marked by gene d.

So, the mother is heterozygous and she can sing well, but can't dance. So her genotype is Ssdd.

The father can't sing and is homozygous, so his genotype is ssDD.

Gametes from the mother is Sd and sd. While the gamete from the father is sD.

So the probabilities of the progenies are SsDd and ssDd.

So the probability of Sean to both sing and dance well is 50%.