Biology 1001A Study Guide - Quiz Guide: Allele Frequency, Genetic Drift, Microevolution

• School: Western University
• Department: Biology
• Course: Biology 1001A
• Professor: Tom Haffie

Document Summary

Phenotypic variation: differences in appearance or function that are passed from generation to generation. Dominance: of an allele describes its effect on the phenotype of heterozygotes not whether the allele is helpful, harmful or neutral, affects evolution rate and outcome. Most genetic disorders are associated with recessive alleles: selection eventually weeds out all copies of a harmful (deleterious) dominant allele form the population, but a harmful recessive allele can hide from selection in heterozygous genotypes. Ex. cheetah inbreeding depression little genetic variation. Quantifying genetic variation: of an individual. Inbreeding coefficient: using pedigrees, of a population. Importance of genetic variation: total amount of genetic variation in the population affects the populations evolutionary potential, shaping individual fitness. Microevolutionary studies: begin by assessing phenotypic variation within population. Blue or white feathers: existence of discrete variants of a character is called a polymorphism. Phenotypic polymorphism quantitatively by calculating the percentage or frequency of each trait. Phenotypic variation can have genetic & environmental causes.