Codominance & Incomplete Dominance

Front

What is codominance?

Back

A genetic scenario where both alleles in a heterozygote are fully expressed, resulting in offspring with a phenotype that is neither dominant nor recessive.

Front

What is incomplete dominance?

Back

A genetic scenario where the phenotype of a heterozygote is intermediate between the phenotypes of the two homozygotes.

Front

Give an example of codominance in humans.

Back

ABO blood type system, where both A and B alleles are expressed in individuals with AB blood type.

Front

Give an example of incomplete dominance.

Back

In snapdragon flowers, crossing red (RR) and white (WW) flowers produces pink (RW) flowers.

Front

What is the phenotype ratio in a codominance cross?

Back

The phenotype ratio is typically 1:2:1 for a monohybrid cross.

Front

What is the phenotype ratio in an incomplete dominance cross?

Back

The phenotype ratio is also typically 1:2:1 for a monohybrid cross.

Front

What is the difference between codominance and incomplete dominance?

Back

In codominance, both traits are fully expressed, while in incomplete dominance, the traits blend to form a new phenotype.

Front

What blood types can result from a cross between a type A and type B parent?

Back

The possible blood types are A, B, AB, and O.

Front

What is a heterozygous genotype?

Back

A genotype consisting of two different alleles for a particular gene.

Front

What is a homozygous genotype?

Back

A genotype consisting of two identical alleles for a particular gene.