Which inheritance pattern involves a trait determined by multiple genes?

Which inheritance pattern involves a trait determined by multiple genes?

• A. Polygenic inheritance
• B. Single-gene inheritance
• C. Sex-linked inheritance
• D. Environmental adaptation

Answer: (A)

Polygenic inheritance involves a trait determined by multiple genes, each contributing a small effect to the overall phenotype. Because several genes add their effects together, you get a continuous range of variation rather than a few discrete categories. This pattern explains quantitative traits like height or skin color, where the trait number varies across a spectrum. The final appearance can also be shaped by environmental factors that influence how the genes are expressed. In contrast, single-gene inheritance produces discrete outcomes based on one gene with clear dominant-recessive relationships, sex-linked inheritance shows patterns tied to sex chromosomes, and environmental adaptation refers to trait changes driven by the environment rather than a fixed multi-gene genetic pattern.

Polygenic inheritance involves a trait determined by multiple genes, each contributing a small effect to the overall phenotype. Because several genes add their effects together, you get a continuous range of variation rather than a few discrete categories. This pattern explains quantitative traits like height or skin color, where the trait number varies across a spectrum. The final appearance can also be shaped by environmental factors that influence how the genes are expressed. In contrast, single-gene inheritance produces discrete outcomes based on one gene with clear dominant-recessive relationships, sex-linked inheritance shows patterns tied to sex chromosomes, and environmental adaptation refers to trait changes driven by the environment rather than a fixed multi-gene genetic pattern.