The pattern of inheritance can be predicted from data if one is given the parent or offspring genotypes or phenotypes. Two organisms, with genotypes BbDD and BBDd, are mated. Assuming independent assortment of the B/b and D/d genes, determine the genotypic ratios in offspring that would occur.
A) 1/2 BBDD, 1/2 bbdd
B) 1/4 BBDD, 1/4 BbDD, 1/4 BBDd, 1/4 BbDd
C) 9/16 BBDD, 3/16 BbDD, 3/16 BBDd, 1/16 bbdd
D) 1/4 BBDD, 1/2 BbDd, 1/4 bbdd

Question

Quizplus · Accepted Answer

The Punnett square for the cross can be made as follows:

B   b
    ------------
D |  BD  bD
d |  BDd bDd

Counting the number of each genotype, we get: 1 BBDD, 1 BbDD, 1 BBDd, and 1 BbDd. Therefore, the genotypic ratios in offspring are 1/4 BBDD, 1/4 BbDD, 1/4 BBDd, and 1/4 BbDd. This corresponds to choice B.

The Pattern of Inheritance Can Be Predicted from Data If