Here's why:
* Heterozygous: Means an individual has two different alleles (versions) of a gene.
* Recessive: A recessive allele only shows its effect if the individual has two copies of that allele (i.e., they are homozygous recessive).
Example:
* Eye color: Brown eyes (B) are dominant to blue eyes (b).
* Heterozygous: A person with Bb genotype will have brown eyes because the dominant B allele masks the recessive b allele.
* Homozygous recessive: A person with bb genotype will have blue eyes because there is no dominant allele to mask the recessive b allele.
