Question

61. Let us assume that hairy toes (hh) and brittle ear wax (ww) are both recessive traits in humans. In families of three children where both parents are heterozygotes at both loci (they have smooth toes and sticky ear wax) what is the probability that the family will consist of one hairy-toed, brittle ear-waxed boy and two smooth-toed, sticky ear-waxed girls

Answer 1

The probability would be 81/32,768

Dihybrid crossing

Both parents are heterozygous at both loci, meaning that their genotype is HhWw.

Crossing two HhWw:

                  HhWw    x     HhWw

Offspring;

H_W_ - smooth toes, sticky earwax = 9/16

H_ww - smooth toes, brittle earwax = 3/16

hhW_ - hairy toes, sticky earwax = 3/16

hhww - hairy toes, brittle earwax = 1/16

Probability of a boy = 1/2

Probability of a girl = 1/2

Probability of having hairy toe, brittle earwax boy = 1/16 x 1/2

                                                                           = 1/32

Probability of smooth toe, sticky earwax girl = 9/16 x 1/2

                                                                        = 9/32

Probability of one hairy-toed, brittle ear-waxed boy and two smooth-toed, sticky ear-waxed girls = 1/32 x 9/32 x 9/32

                                    = 81/32,768

More on dihybrid crosses can be found here: https://brainly.com/question/1185199