An individual that is heterozygous for type B blood and little finger shape mates with an individual that is heterozygous for type A blood and homozygous dominant for a bent little finger. What is the predicted genotypic ratio for this cross?
A. 9:3:3:1
B. 1:2:1
C. 1:1:1:1:1:1:1:1
D. 2:1:2:1:4:1:2:1
E. 1:1:1:1

The correct option is E) 1:1:1:1

Explanation:

A punnet square in which only a single trait is being studied is a monohybrid cross. A cross in which two traits are being studied in a dihybrid cross.

As two traits are being studied in the question, hence a dihybrid cross will be made as follows:

          A-F     A-F     OF         OF

Bf     ABFf    ABFf      BOFf      BOFf

Bf    ABFf     ABFf      BOFf      BOFf

Of    AOFf    AOFf      OOFf     OOFf

Of    AOFf    AOFf      OOFf     OOFf

The results of the punnet square show that there are

Hence, there will be an equal ratio of 1:1:1:1 for each of the genotype.

b.have there own function.

this is true, assuming that the allele is completely recessive and incomplete dominance is not a factor.