unit 7 apbio V.short

Describe the causes of natural selection.

overproduction of offspring

limited resources/competition

differential reproductive success ("fitness")

Explain how natural selection affects populations

evolutionary fitness measured by reproductive success

biotic (organic) and abiotic (inorganic) environments

different genetic variations

Describe the importance of phenotypic variation in a population.

Environments change and apply selective pressures to populations

Explain how humans can affect diversity within a population.

population numbers, use of land, and their lifestyles, causing damage to habitats for species.

Explain the relationship between changes in the environment and evolutionary changes in the population

Change in an populations environment forces the population to adapt to fit the new environment, eventually causing it to evolve into a new species.(enviromental pressures)

Explain how random occurrences affect the genetic makeup of a population.

changes the gene pool of a population by providing chance mutations and other random occurences that provide more genetic diversity.

Describe the role of random processes in the evolution of specific populations

allow populations to adapt better to their enviroment and allow for more genetic diversity within a population. this leads to the evolution of a population.

Describe the conditions under which allele and genotype frequencies will change in populations.

Selection, mutation, migration, and genetic drift are the mechanisms that effect changes in allele frequencies

Explain the impacts on the population if any of the conditions of Hardy-Weinberg are not met.

the population may be evolving for that gene and the gene's allele frequencies are changing

Describe the types of data that provide evidence for evolution.

morphological (the structures of organisms living and extinct)

biochemical (fundamental/celluar features are conserved across organisms)

geological(the distrubution of animals and plants across earth)

Describe structural and functional evidence on cellular and molecular levels that provides evidence for the common ancestry of all eukaryotes

membrane bound organelles, intions and linear chromosomes

Describe the fundamental molecular and cellular features shared across all domains of life, which provide evidence of common ancestry.

morphological data, geological data, fossils- helps us tell the age of the rock, carbon 14 dating, homologies between different structures and DNA all help link together to show that we have a common ancestor

Explain how evolution is an ongoing process in all living organisms

genomic changes (Genome evolution is the process by which a genome changes in structure (sequence) or size over time)

continuous change in the fossil record

resistance to antibiotics, pesticides, herbicides or chemotherapy drugs

Describe the types of evidence that can be used to infer an evolutionary relationship.

phylogenetic trees and cladograms

traits gained or lost

molecular data (DNA and the genetic code reflect the shared ancestry of life. DNA comparisons can show how related species are)

Explain how a phylogenetic tree and/or cladogram can be used to infer evolutionary relatedness.

A phylogenetic tree shows the evolutionary history of a certien group of organisms

A cladogram shows how different species could've been derived from a common ancestor

Describe the conditions under which new species may arise.

New species arise through a process called speciation. In speciation, an ancestral species splits into two or more descendant species that are genetically different from one another and can no longer interbreed.

Describe the rate of evolution and speciation under different ecological conditions.

punctuated equilibrium (nothing happens then rapid evolution) vs gradualism (slowly over time)

divergent evolution (gain differences over time)

Explain the processes and mechanisms that drive speciation.

It occurs when groups in a species become reproductively isolated and diverge

Describe the factors that lead to extinction of a population.

habitat loss, an introduced species, pollution, population growth, and overconsumption.

Explain how the risk of extinction is affected by changes in the environment.

changes in enviroment leads to more enviromental pressures for a species. if there are too many enviromental pressures then a species can't adapt and it leads to it being extinct.

Explain how species diversity in an ecosystem as a function of speciation and extinction rates.

species diversity in a ecosystem allows for more speciation, however this also leads to more compitition over certain niches in an enviroment. this compitition can lead to extinction of a species that isnt fit enough to survive in the new enviroment.

Explain how extinction can make new environments available for adaptive radiation

extinction leads to niches forming in a habitat, this allows species to diversify more rapidly to fill those niches in the enviroment

Explain how the genetic diversity of a species or population affects its ability to withstand environmental pressures.

The more genetic diversity there is in a population, there is a higher likelyhood of the species being able to withstand enviromental pressures. this is because the more diversity there is the more likely there is an adaptation already in the population that is able to withstand the new enviromental pressures.

Describe the scientific evidence that provides support for models of the origin of life on Earth.

RNA world hypothesis

endosymbiant theory

synthesis of organic organisms

Describe the change in the genetic makeup of a population over time.

over time, a populations genetic makeup/ gene pool will grow through random events and diversify.