Question

Describe the differences between dominance, co-dominance, and incomplete dominance.

Answer 1

1. Dominance (complete dominance) would be a case in which 1 allele is always dominant over the other(s).

Example: we could see this clearly when breeding to homozygous dominant organisms (offspring are always dominant).

2. Co-dominance would be a case in which a combination of alleles is always dominant over the other combination(s).

Example: we could see this when breeding to dalmatian dogs, where both black and white colours are dominant.

3. Incomplete dominance would be a case in which it is not a fully dominant allele but it is still more dominant than the other allele(s).

Example: we could see this when breeding a red (dominant) and white (recessive) rose. The outcome will be pink, because red isn't dominant enough to make the outcome red.

Hope it helped,

BiologiaMagister

Answer 2

See below

Step-by-step explanation:

Dominance: One trait is dominant to another, this trait is expressed. For example: DD - two (identical) dominant traits, dominant trait expressed. Dd - One dominant trait, dominant trait is still expressed. dd - recessive traits, this is the only case where a recessive trait can be expressed since there is no dominant trait to block it.

This is what happens most of the time, with some exceptions (explained below)

However:

Co-dominance: Two dominant traits, both are expressed. For example, this is seen in the roan coat color in animals such as cattle and horses. Both the red and white coat colors of the parents are expressed (the coat visibly contains both red and white)

Incomplete dominance: The dominant trait doesn't completely override the recessive trait. For example, this is seen in some types of flowers. Imagine the parent plants of a plant produce red and white flowers respectively, but the plant that they produced has pink flowers. Incomplete dominance results in a "blending", but neither trait is fully expressed

Hope this helps!

Source: this is very similar to how my biology teacher explained it.