BIOL 1001 Chapter Notes - Chapter 17: Heterozygote Advantage, Gene Flow
Document Summary
Phenotypic variation- differences in appearance or function that are passed from generation to generation- animals within a species can differ in anatomy and behavior, this is caused by phenotypic variation. Quantitative variation- when individuals differ in small, incremental ways (e. g. height of individuals, amount of hair). This is usually graphed as a bar, and as a curve with a large sample. Width of the curve is proportional to the variability; mean describes the average value of the character. Qualitative variation- they exist in two or more discrete states, there is no intermediate between them (e. g. geese can have either white or blue feathers, there is no blending). Polymorphism- when there is discrete variant characters (e. g. a, b, ab, o blood types); we calculate polymorphisms by calculating percent frequencies of each trait. Phenotypic variation can be caused by genetic differences, environmental factors, or interaction between genetics and environment (more likely). Organisms with different genotypes can result in the same phenotype.