Question

Referring to two genes of one pair that differ in some way typically one allele has only a few base pairs that differ from the other member of the pair

A) Codominance
B) Incomplete dominance
C) Heterozygous
D) Homozygous

Answer 1

Codominance occurs when both alleles for the same characteristic are simultaneously expressed in a heterozygote, as seen in the MN or ABO blood groups of humans.

Step-by-step explanation:

When two genes of a pair differ from each other, and both alleles are expressed in the heterozygote, this is known as codominance. An example of this is seen in the MN blood groups of humans, where individuals with the heterozygous genotype (LMLN) express both the M and N alleles equally. This differs from incomplete dominance, where the phenotype of the heterozygote is intermediate between the phenotypes of the homozygotes. The ABO blood type system is a classic example of codominance with multiple alleles present at the population level, where individuals with the AB blood type express both the A and B alleles (IAIB).