What is the basis of codominance?

Question

What is the basis of codominance?

A) One allele of a gene encodes a protein, the other allele is nonfunctional.

B) One gene has many effects.

C) One gene has many alleles.

D) Each allele of a gene produces a protein that functions to create a trait.

E) There is only one allele for a gene.

Answer 1

D

Codominance means neither trait is recessive.  So when both alleles are there, they will both have an effect on the phenotype.