Which term means three or more forms of a gene that code for a single trait?

Which term means three or more forms of a gene that code for a single trait?

• A. Alleles
• B. Codominance
• C. Polygenic traits
• D. Multiple alleles

Answer: (D)

The concept here is variation at a single gene locus. When a population has three or more different forms of a gene that can occupy the same spot on a chromosome and influence one trait, that situation is called multiple alleles. This term specifically captures the idea of more than two possible gene versions contributing to a single trait. For example, the ABO blood group system uses three alleles (two coding for A and B antigens and one for no antigen), which together produce four possible blood types. This differs from the general idea of alleles, which are any alternate forms of a gene; codominance describes how two different alleles are both expressed in a heterozygote; and polygenic traits involve multiple genes influencing a trait.

The concept here is variation at a single gene locus. When a population has three or more different forms of a gene that can occupy the same spot on a chromosome and influence one trait, that situation is called multiple alleles. This term specifically captures the idea of more than two possible gene versions contributing to a single trait. For example, the ABO blood group system uses three alleles (two coding for A and B antigens and one for no antigen), which together produce four possible blood types. This differs from the general idea of alleles, which are any alternate forms of a gene; codominance describes how two different alleles are both expressed in a heterozygote; and polygenic traits involve multiple genes influencing a trait.