Incomplete Dominance vs. Codominance

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

What is codominance?

Back

A genetic scenario where both alleles in a heterozygote contribute equally and visibly to the phenotype.

Front

Provide an example of incomplete dominance.

Back

An example is the flower color in snapdragons, where red and white flowers produce pink offspring.

Front

Provide an example of codominance.

Back

An example is the AB blood type in humans, where both A and B alleles are expressed.

Front

How do phenotypes differ in incomplete dominance compared to codominance?

Back

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

Front

What is the expected phenotype ratio in a monohybrid cross exhibiting incomplete dominance?

Back

The expected phenotype ratio is 1:2:1 (one homozygous dominant, two heterozygous, one homozygous recessive).

Front

What is the expected phenotype ratio in a monohybrid cross exhibiting codominance?

Back

The expected phenotype ratio is also 1:2:1, but all phenotypes are distinct.

Front

In codominance, how do the alleles behave in a heterozygous individual?

Back

Both alleles are expressed equally and contribute to the phenotype.

Front

What is a key difference between incomplete dominance and codominance in terms of genetic expression?

Back

Incomplete dominance results in a blended phenotype, while codominance results in distinct expression of both alleles.

Front

Can you have a situation where neither incomplete dominance nor codominance occurs?

Back

Yes, in complete dominance, one allele completely masks the effect of the other.