Question

Which correctly pairs the phenotype expression with their description :incomplete dominance a third in between phenotype is expressed or codominancebith phenotype are expressed simultaneously

Answer 1

Incomplete dominance occurs when a heterozygote's phenotype is a blend of homozygous phenotypes. Codominance happens when both alleles are equally expressed in a heterozygote, as seen with human blood types M and N. Both patterns deviate from traditional dominant-recessive genetics.

Step-by-step explanation:

The student is asking about the difference between incomplete dominance and codominance, two patterns of inheritance that deviate from the traditional dominant-recessive inheritance. In incomplete dominance, the phenotype of heterozygotes is an intermediate blend of the homozygous phenotypes. For instance, if a red-flowered plant is crossed with a white-flowered plant, the offspring might display pink flowers, which is the intermediate phenotype, neither red nor white.

On the other hand, codominance is characterized by the simultaneous expression of both alleles in a heterozygote. An example is the human MN blood group system. If an individual inherits one M allele from one parent and one N allele from the other, both alleles are expressed equally, resulting in blood cells that have both M and N antigens.

In summary, incomplete dominance results in a third phenotype that is a mix of both parental types, while in codominance, both parental phenotypes are expressed equally and simultaneously in the offspring.