Selection and evolution

VariationSign up

understand how phenotype results from the interaction of genotype and environment · know how epigenetic modification (DNA methylation, histone modification) can alter gene activation and be passed on following cell division · understand how phenotypes are affected by multiple alleles for the same gene, by polygenic inheritance, and by the environment, giving rise to continuous variation

Natural Selection, Allele Frequencies and the Hardy-Weinberg PrincipleSign up

understand the concept of niche; discuss adaptations of organisms (behavioural, anatomical, physiological) · understand how the Hardy-Weinberg equation tracks allele frequency changes in a population over time · understand that changes in allele frequency arise from mutation and natural selection · understand that reproductive isolation can lead to accumulation of different genetic information in populations and the formation of new species

Selective Breeding (Artificial Selection)Sign up

17.2.6: describe the principles of selective breeding (artificial selection) - humans choosing parents with desirable phenotypes, breeding them, selecting the best offspring, and repeating over many generations to shift allele frequencies in the desired direction · 17.2.7: outline the introduction of disease resistance to varieties of wheat and rice · 17.2.7: outline inbreeding and hybridisation (including hybrid vigour) to produce vigorous, uniform varieties of maize · 17.2.7: outline improving the milk yield of dairy cattle (use of progeny testing / artificial insemination)

Evolution and SpeciationSign up

understand how evolution (changes in allele frequency) can come about through gene mutation and natural selection · understand how isolation reduces gene flow between populations, leading to allopatric or sympatric speciation · understand how scientific conclusions on controversial issues (climate change actions, human contribution) can depend on who is reaching the conclusions · understand how reforestation and the use of sustainable resources (including biofuels) manage the conflict between human needs and conservation