What does a homozygote refer to in genetics?

A homozygote refers to an organism that possesses two identical alleles for a particular gene. This means that both chromosomes in a homologous pair carry the same version of the gene, whether it is a dominant or recessive allele. For example, if a plant has two alleles for flower color that are both "purple" (PP) or both "white" (pp), it is considered homozygous for that trait.

Recognizing the importance of homozygosity is crucial in genetics, as it can influence an organism's phenotype, or observable traits. Homozygous individuals tend to consistently express certain traits because there is no alternative allele that could produce variation in the trait. This contrasts with organisms that are heterozygous, which contain two different alleles for a gene, leading to potential variation in how traits will be expressed based on dominance relationships between alleles.