Answer:
- Complete dominance: one allele masks the expression of the other gene variant or the phenotype is caused by the absence of gene function when both alleles are recessive.
- Incomplete dominance (codominance): both alleles are expressed and contribute to the phenotype
Explanation:
Complete dominance is a type of dominance by which one allele (dominant allele) completely masks the effects of another allele (recessive allele) in heterozygous individuals (i.e., individuals carrying two different gene variants or alleles). On the other hand, codominance refers to a type of incomplete dominance where both alleles in the genotype are observed in the phenotype. Complete dominance is caused when the recessive allele is not expressed, while if both alleles are expressed it is called incomplete dominance.