Evolution
What occurs during the founder effect?
A few individuals establish a new population.
What is the significance of the rainshadow effect?
Mountains block moist air, creating dry regions on the leeward side.
Difference between genotypic and phenotypic variation?
Genotype: Differences in allele combinations
Phenotype: Observable trait differences produced by genotypic variation.
What is the order of levels of ecological organization?
Organism → Population → Community → Ecosystem → Biosphere.
Difference between abiotic and biotic factors?
Abiotic: Non-living components of the environment, such as temperature, water availability, and light intensity.
Biotic: Living components of the environment, such as predators, prey, and competitors.
What does Hardy-Weinberg equilibrium describe?
A non-evolving population with five conditions that must hold simultaneously.
What is the bottleneck effect?
Drastic population reduction leading to survivors' alleles not representing the original population.
What is an assumption of Hardy-Weinberg equilibrium?
No mutations.
Difference between r-selected and K-selected species?
R-selected: Many offspring, little parental care.
K-selected: Few offspring, high parental investment.
What is the significance of homologies in evolution?
They provide evidence for evolutionary relationships.
What are habitat corridors?
Connections between fragmented habitats that allow animal movement and maintain gene flow.
What are the sources of genetic variation?
Mutation, independent assortment, crossing over, random fertilization, and horizontal gene transfer.
Difference between directional selection and stabilizing selection?
Directional Selection: One extreme phenotype.
Stabilizing Selection: Intermediate phenotypes.
What determines biome distribution globally?
Latitude affects solar radiation, which drives temperature and precipitation.
What does the biological species concept define and what can it not apply to?
Define: Populations that interbreed and produce fertile offspring.
Not applicable: Fossils.
What did Lamarck propose about evolutionary change?
Inheritance of acquired characteristics.
Difference between parasitism, mutualism, predation
parasitism: An interaction where a parasite feeds on a host without killing it immediately.
mutualism: An interaction where both species benefit.
Predation: An interaction where one species (predator) feeds on and kills another (prey).
What is a prezygotic barrier, and what is an example of one?
A prezygotic barrier prevents mating attempts. ex: Gametic isolation.
What is the role of fire in temperate grasslands?
Fire maintains the ecosystem by preventing tree establishment and promoting grass growth.
What does polyploidy most commonly cause?
Instant sympatric speciation in plants.
What is the IUCN Red List?
A global system used to prioritize conservation action based on species' extinction risk.
What is the significance of Thomas Malthus' work?
It focused on population growth and resource limitation, influencing Darwin and Wallace.
What occurs during allopatric speciation?
Populations become geographically isolated.
What are the three components of biodiversity?
Genetic diversity, species diversity, and ecosystem diversity.
What results from disruptive (diversifying) selection?
Favoring of two or more distinct phenotypes.