Answer:
Parents: Yellow (Aarr) and Grey (AaRr)
Explanation:
Given:
allele A = yellow
allele R = black,
Heteroozygous = gray
Genotypes of the parents:
yellow (Aarr) - female
gray (AaRr) - gray
cross between these
Parents: Yellow (Aarr) and Grey (AaRr)
Gametes: (Ar, ar) and (AR, Ar, aR, ar)
F1 (Punnet square)
----|----- AR ------|------- Ar ------|------ aR -----|----- ar
Ar | AARr (gray) | AArr (yellow) | AaRr (gray) | Aarr (yellow)
ar | AaRr (gray) | Aarr (yellow) | aaRr (black) | aarr (cream)
Ratio: 3/8 yellow : 3/8 gray : 1/8 cream : 1/8 black