AP BIOLOGY

Detailed explanation-1: -Phenotypes of traits can often be graphed and demonstrate a bell-shaped distribution. Polygenic traits tend to result in a distribution that resembles a bell-shaped curve, with few at the extremes and most in the middle. There may be 4 or 6 or more alleles involved in the phenotype.

Detailed explanation-2: -These traits have what’s called continuous variation, showing a bell curve of values for the phenotype. This is because there are multiple genes that play a role in the phenotype, and each gene could have multiple alleles. This can give a range of possible phenotypes from all the variation that’s coming into play here.

Detailed explanation-3: -Polygenic inheritance often results in a bell shaped curve when you analyze the population. That means that most people fall in the middle of the phenotypic range, such as average height, while very few people are at the extremes, such as very tall or very short.

Detailed explanation-4: -Human phenotypes such as hair color, eye color, height, and weight are examples of polygenic traits. Complex diseases (e.g., cardiovascular diseases, Alzheimer’s, and Schizophrenia) also have a polygenic basis. Human hair color is an example of a polygenic trait.

Detailed explanation-5: -Natural selection can act on traits determined by different alleles of a single gene, or on polygenic traits (traits determined by many genes). Polygenic traits in a population often form a bell curve distribution.