Question

Bear pigmentation is subject to epistasis of the B alleles by the d alleles. B (black) is dominant over b (brown). D is dominant over d. Homozygous d is epistatic to the black and brown genes. Given this information, what will result from a F1 cross between two bears

Answer 1

Answer:

9/16 black, 3/16 brown, 4/16 white

Explanation:

             BD         Bd          bD         bd

BD     BBDD      BBDd     BbDD     BbDd

Bd      BBDd      BBdd     BbDd      Bbdd

bD      BbDD     BbDd      bbDD     bbDd

bd       BbDd    Bbdd       bbDd     bbdd

A punnet square can be described as a diagram which is made to predict the genotype as well as the phenotypes of the offsprings of a cross.

To study the epistatis nature of the pigmentation in bear, a punnet square was made and the results of the punnet square are shown above.

The results of the punnet square show that the cross between two bears will have the chances of producing 9/16 black bears, 3/16 brown bears and 4/16 white bears.