Two identical alleles define which zygosity?

Two identical alleles define which zygosity?

• A. Homozygous
• B. Heterozygous
• C. Allele
• D. Genotype

Answer: (A)

Zygosity describes whether the two copies of a gene at a specific location are the same or different. When they are identical, the organism is homozygous for that gene. If the copies are different, it is heterozygous. Since two identical alleles define being homozygous, that term is the appropriate label here. An allele is a single variant of a gene, and genotype refers to the overall genetic makeup across many genes, not just the relationship between the two alleles at one locus. For example, BB or bb are homozygous, while Bb is heterozygous.

Zygosity describes whether the two copies of a gene at a specific location are the same or different. When they are identical, the organism is homozygous for that gene. If the copies are different, it is heterozygous. Since two identical alleles define being homozygous, that term is the appropriate label here. An allele is a single variant of a gene, and genotype refers to the overall genetic makeup across many genes, not just the relationship between the two alleles at one locus. For example, BB or bb are homozygous, while Bb is heterozygous.