Question

Suppose that a rabbit breeder notices two individuals in a litter with large, round noses and names this trait the clown trait. He obtains another rabbit that has a long, thin nose and names it the Pinocchio trait. After breeding the rabbits with unusual nose shapes to wildâtype individuals for several generations, he decides to cross rabbits from families with a history of the clown and Pinocchio traits. The first litter from this cross results in individuals of four phenotypes. The phenotypes are clown, Pinocchio, wildâtype, and heartâshaped noses. The pedigree illustrates the inheritance of these traits. Individuals 1 and 4 are siblings and are known to come from a true-breeding wild type line.

1. What is the most likely mode of inheritance for the clown nose?

a. -linked
b. X-linked dominant
c. X-linked recessive
d. Autosomal dominant
e. Autosomal recessive

2. What is the most likely mode of inheritance for the Pinocchio nose?

1. Sex-influence
2. X-linked dominant
3. X-linked recessive
4. Autosomal dominant
5. Autosomal recessive

Answer 1

1. The probable method of inheritance for the nose is a male chromosome-linked recessive.

2. The probable method of inheritance for the Pinocchio nose is in the autosomal chromosomes, with a dominance factor.

Step-by-step explanation:

1. The gene is observed to be expressed in males.

2. The gene of Pinocchio expression has been expressed from the parents with equal phenotype.