Question

final step - based on the genotype of the baby, what must the genotype of the solid grey parent be? (hint: if you are not sure, put both possibilities in two different punnet squares and see which one gives you a spotted baby!) ss homozygous dominant ss heterozygous ss homozygous recessive

Explanation:

A spotted baby implies it has a recessive - trait genotype. For a recessive - trait to appear in the offspring, both parents must contribute at least one recessive allele. If the solid grey parent is homozygous dominant (SS), it can only pass on a dominant allele and will not produce a spotted baby. If it is homozygous recessive (ss), it is spotted itself, which is not the case as it is solid grey. A heterozygous (Ss) parent can pass on a recessive allele, which, when combined with another recessive allele from the other parent, can result in a spotted baby.

Answer:

B. Ss heterozygous