Which statement correctly defines genotype and phenotype?

Which statement correctly defines genotype and phenotype?

• A. Phenotype is alleles; genotype is expressed trait
• B. Genotype is allele combination; phenotype is expressed trait
• C. Genotype is phenotype; phenotype is genotype
• D. They are unrelated

Answer: (B)

Genotype refers to the genetic makeup—the specific alleles an individual carries for a gene. Phenotype is the observable trait that results from the expression of those alleles, and it can be influenced by the environment as well. So describing genotype as the allele combination and phenotype as the expressed trait captures the fundamental distinction: the genotype is the inherited genetic code, while the phenotype is what you can see or measure. For example, in a simple trait, the genotype might be homozygous or heterozygous for a color allele, and the phenotype is the color you observe. The other statements mix up these ideas or claim they’re unrelated, which isn’t accurate.

Genotype refers to the genetic makeup—the specific alleles an individual carries for a gene. Phenotype is the observable trait that results from the expression of those alleles, and it can be influenced by the environment as well. So describing genotype as the allele combination and phenotype as the expressed trait captures the fundamental distinction: the genotype is the inherited genetic code, while the phenotype is what you can see or measure.

For example, in a simple trait, the genotype might be homozygous or heterozygous for a color allele, and the phenotype is the color you observe. The other statements mix up these ideas or claim they’re unrelated, which isn’t accurate.