Rooster with specific comb morphology called walnut was crossed to a hen with a type of comb morphology known as single. The F1 progeny all had walnut combs. WHen F1 males and females were crossed to each other the following occured:

93 walnut combs
11 single combs
Twenty Nine rose combs (a new comb type)
Thirty Two pea combs ( another new comb type_

(a) explain how comb shape is inherited. It is determined by one gene or two? If it is one gene it is dominant if it is two, indicate the gene interation that results each phenotype.

(b) What progeny would result from crossing a pure-bred rose combed hen with dihybrid walnut rooster? Give the genotypes of the parents and the genotpye and phenotypes of the F1.