In chickens, the allele for a pea comb (A) is dominant to the allele for a single comb (a).
A mother with the genotype Aa and a father with the genotype Aa produce an offspring.
What is the percent chance that the offspring will have a single comb?

In chickens, the allele for a pea comb (A) is dominant to the allele for a single comb (a).  A mother with the genotype Aa and a father with the genotype Aa produce an offspring.  What is the percent chance that the offspring will have a single comb?

A= Pea comb

a= single comb

Aa x Aa= AA, Aa, Aa and aa

The percentage of having offspring with single comb is 25% as others with pea comb makes 75% with two homozygous (Aa dominant pea comb and aa  recessive single comb) and two heterozygous (Aa and Aa)

Explanation:

The percentage chance that the offspring will have a single comb is 25%

Explanation: A cross between a mother with genotype Aa and a father with genotype Aa will produce four offsprings: 1AA, 2Aa and 1aa, i.e., Aa x Aa = AA, Aa, Aa and aa.

Genotypes AS and Aa will manifest as pea comb while genotype aa will manifest as single comb. This means that one offspring out of the four has a single comb.

Therefore, the percentage chance of having an offspring with a single comb is 1/4 x 100 = 25%

Punnet square

- A a

A AA AA

a Aa aa