What term describes having two different alleles for the same gene?

What term describes having two different alleles for the same gene?

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

Answer: (C)

Having two different alleles for the same gene is heterozygosity. In diploid organisms, each gene has two alleles, one from each parent. When those alleles are different—like one version for a trait and a different version—the genotype is heterozygous for that gene. This can affect how the trait is expressed, depending on which allele is dominant or recessive. If the two alleles are the same, the organism is homozygous for that gene. Genotype simply describes which alleles are present and can be either homozygous or heterozygous. Purebred describes breeding history and often implies two copies of the same allele for particular traits, but it doesn’t define having two different alleles for one gene.

Having two different alleles for the same gene is heterozygosity. In diploid organisms, each gene has two alleles, one from each parent. When those alleles are different—like one version for a trait and a different version—the genotype is heterozygous for that gene. This can affect how the trait is expressed, depending on which allele is dominant or recessive. If the two alleles are the same, the organism is homozygous for that gene. Genotype simply describes which alleles are present and can be either homozygous or heterozygous. Purebred describes breeding history and often implies two copies of the same allele for particular traits, but it doesn’t define having two different alleles for one gene.