BI111 Chapter Notes - Chapter 68: Hbb, Point Mutation, Hemoglobin
Document Summary
Changes in allele freq. can occur in pop over successive generations when variations in heritable traits cause differences in reproductive success. Phenotype from mutated gene confers higher fitness, more of that gene will be present in next generation. Adaptation: heritable trait that increases ind fitness. Example: monarch butterflies brightly coloured to seem toxic to predators & incorporate milkweed toxins in tissues. Bird eats, it pukes, will remember the butterfly. Other butterflies mimic monarch, thus predators avoid. Passage of heritable traits that increased fitness of species altered allele freq. Recognition that there is limit to # of ind in given pop b/c # of resources available to support pop are limited. Struggle for existence: when ind compete for resources. Organism reproduce by passing their genes to next gen. Genetic variation b/w ind in a pop leads to trait variation. F(cid:396)e(cid:395). of alleles inc(cid:396)eases as it"s passed to next gen = adaptation. Natural selection can cause deleterious alleles to remain in pop.
