Question

A siamese cat can be one of three colors. Black(B) , Orange (O) or black and orange(BO).

What will be the result of crossing a purebred orange siamese cat with a hybrid (BO)?
Offspring Genotypes
Offspring phenotypes?
What type of inheritance is this?

Answer 1

Offspring Genotypes - ½ BO : ½ OO

Offspring phenotype - ½ Black orange cat : ½ orange cat

Type of inheritance - Co-dominance

Step-by-step explanation:

This question involves a single gene coding for skin color in Siamese cat. The alleles for orange color (O) and black color (B) are co-dominant i.e. they are both expressed in a heterozygous state.

According to the question, a purebred orange siamese cat (OO) was crossed with a hybrid cat (BO). The following gametes will be produced by each parent:

OO - O only

BO - B and O

Using these gametes in a punnet square (see attached image), the following proportion of offsprings will be produced from this cross:

½ BO : ½ OO

½BO - Black orange phenotype

½OO - Orange phenotype

- This type of inheritance is CO-DOMINANCE