Question

Differentiate between the following:

Co-dominance and Incomplete dominance

Answer 1

Basis of Difference	Co-dominance	Incomplete dominance
Expression in a heterozygote	In co-dominance, both alleles express fully and equally in the heterozygote.	In incomplete dominance, neither allele is completely dominant, so the heterozygote shows an intermediate trait.
Appearance of the heterozygote	The heterozygote displays both parental traits together.	The heterozygote displays a phenotype intermediate between the parental traits.
Example	In the human ABO blood group system, genotype IAIB produces blood group AB, with both A and B antigens.	In snapdragons, crossing red and white flowers produces pink heterozygous flowers.
Typical F2 ratio	In the standard example, the offspring phenotypes depend on the alleles and their combinations.	In snapdragons, the F2 phenotypic ratio is 1 red : 2 pink : 1 white.