What does genotype refer to?

What does genotype refer to?

• A. The combination of alleles an organism inherits.
• B. The observable trait expressed.
• C. The physical location of a gene on a chromosome.
• D. The number of chromosomes in a gamete.

Answer: (A)

Genotype is the genetic makeup—the specific alleles present for a gene. It’s the two alleles an organism inherits for that gene, which can be homozygous (same allele on both chromosomes) or heterozygous (two different alleles). This differs from phenotype, the observable trait that results from how those alleles are expressed, often influenced by environment. The location of a gene on a chromosome is its locus, a separate concept, and the number of chromosomes in a gamete reflects the haploid set, not the genotype. So, the mix of alleles an organism carries defines its genotype.

Genotype is the genetic makeup—the specific alleles present for a gene. It’s the two alleles an organism inherits for that gene, which can be homozygous (same allele on both chromosomes) or heterozygous (two different alleles). This differs from phenotype, the observable trait that results from how those alleles are expressed, often influenced by environment. The location of a gene on a chromosome is its locus, a separate concept, and the number of chromosomes in a gamete reflects the haploid set, not the genotype. So, the mix of alleles an organism carries defines its genotype.