AP Biology Vocabulary

Taxonomy

science of classification

Disruptive selection

Favours extreme

Stabilizing selection

Favours centre

Directional selection

Favours 1 extreme

Behavioural isolation

Don't recognizing mating/courting behaviours

Mechanical isolation

Morphology doesn't line up

Temporal isolation

Breed at different times

Gametic isolation

Egg and sperm don't recognize eachother

Habitat isolation

Live in different habitats and do not meet

Gene flow

movement of alleles

Reduced hybrid viability

Make but won't develop

Reduced hybrid fertility

Develop but can't reproduce

Hybrid breakdown

Reproduce but offspring are weaker

Morphological species

defined by structure

Ecological species

defined by ecological niche

Phylogenetic species

smallest group of organisms that share a common ancestor

Evidence supporting evolution

Comparative anatomy, fossil record, DNA sequencing, documented observations of evolution

Homologies (related to comparative anatomy)

Shared characteristics because of common ancestry

Vestigial structures

A structure that is present but no longer serves its original purpose

Homologous structures (divergent)

Same structure, different function

Analogous structures (convergent)

Different structure, same function

What do fossil records show

change, origins, extinctions

Evolution

gradual change to improve fitness

Niche

organisms "job" in the ecosystem

Artificial selection

Selective breeding to have desirable traits in offspring (humans)

Natural selection

Environment chooses the favourable traits

Adaptations

changes in structure, function, or behaviour that improve fitness

Genetic variation

Different types of genes in a species or population

Reproductive success

Likelihood of an individual contributing fertile offspring to the next generation

Heritability

Ability of a trait to be passed on

extant

Exists

extinct

No longer exists

species

A group of organisms that are closely related and can successfully mate

Eukaryotes common ancestry evidence

membrane-bound organelles, linear chromosomes, genes that contain introns

Reasons for evolution

genomic changes, fossil record changes, resistance to things, pathogens

Genomic

study of genomes (genes and their functions)

pathogens

organisms that cause disease

Mutations

a random error in gene replication that leads to a change

Sexual reproduction and genetic variation

mutations (meiosis), crossing over and fertilization (biggest sources)

Microevolution

changes in allele frequencies

Genetic drift

random change with allele frequencies

Conditions of Hardy-Weinberg

No mutation, random mating, large pop. size, no gene flow, no natural selection

Phylogenetic

evolutionary relatedness

speciation

Formation of new species

bottleneck effect (genetic drift)

sudden environmental change causes pop. reduction

founder effect (genetic drift)

few individuals become isolated

Allopatric speciation

speciation that occurs with geographic isolation

Sympatric speciation

Speciation without a divided population (factors are sexual selection, new niches because of habitat differentiation, polyploidy)

Polyploidy

organism has extra sets of chromosomes (can be fertile and create new species)

Adaptive radiation

An evolutionary pattern: many species evolve from a single species

Why are speciation rates often rapid in situations where adaptive radiation occurs or during times of ecological stress?

ecological opportunities or environmental pressures drive rapid adaptation to new niches or survival strategies

- increase is also caused by genetic variation, isolation of populations, and strong selection pressures

Connection between speciation and change in gene frequency, change in the environment, natural selection, and genetic drift

no gene flow, adaptations to new conditions, reproductive isolation (diverging traits), random allele changes (genetic drift)

3 domains of life

archea, bacteria, and eukarya

Process the the 3 domains share

DNA replication and cellular respiration

Scientific hypothesis about the origin of life on earth

abiotic synthesis of small molecules, joining into macromolecules, packaging of molecules into protocells (droplets with consistent internal chemistry), and origin of self-replicating molecules

Age of Earth (when did proka and eukar emerge)

Earth is 4.6by, prokaryotes is 3.5by, and eukaryotes is 1.8by

maximum parsimony

simplest phylogenetic tree

Characteristics of early planet

lack of oxygen, lots of gases (nitrogen and methane), volcanic eruptions

How Miller and Urey tested the Oparin-Haldane hypothesis and what they learned

mixed basic compounds with electric voltage to show that creating organic molecules is possible

Polymerization

large molecules of repeating monomers (small molecules) e.g. proteins (amino acids are the monomers)

Continental drift can explain distribution of species

continents were once connected so species could spread before they became geographically isolated --> species evolved separately leading to the distinct flora and fauna

How extinction events open habitat that may result in adaptive radiation

fewer competitors, more ecological niches vacant --> surviving species can rapidly diversify to fill new niches, leading to evolution

RNA

probably the first genetic material (RNA --> protein is the origin of life)

Endosymbiotic theory

certain kinds of prokaryotes began living inside larger cells and evolved into the organelles of modern-day eukaryotes