COMPLETE notbook lm flashcards

What is a biome?

A large naturally occurring community of flora and fauna occupying a major habitat, e.g., forest or tundra. Climate shapes the nature and distribution of biomes.

What causes the temperature to drop with increased elevation?

Temperature tends to drop about 6.5°C per kilometre in elevation due to the decreasing density of the atmosphere and the reduced ability to retain heat.

What primarily causes seasons?

Seasons are caused by the Earth's tilt on its axis, not by its elliptical orbit or varying distance from the sun.

What is the Coriolis effect?

The deflection of moving objects when they are viewed from a rotating frame of reference, like the Earth. This affects wind patterns and ocean currents.

What is evapotranspiration?

The sum of evaporation from soils and water bodies plus the amount of water transpired by plants. The ratio of evapotranspiration and precipitation determines biomes.

What is convergent evolution?

The independent evolution of similar structures in unrelated organisms due to similar environmental pressures.

Describe the tundra biome.

The coldest biome, located near the North Pole, with short days in winter limiting the growing season.

Describe a deciduous forest.

Forests with trees that lose their leaves at the end of the growing season, featuring moderate temperatures and precipitation all year round.

Describe the savanna biome.

Dominated by tall grasses, has seasonal rainfall, and is found in eastern Africa, southern South America, and Australia.

What is a key factor influencing aquatic biomes?

The depth to which sunlight penetrates water, influencing primary producers and food webs.

What are the main types of aquatic biomes?

Freshwater, estuary, and saltwater biomes.

What are characteristics of a river biome?

Rivers and streams are freshwater biomes characterised by moving water.

What is an estuary?

An ecotone between freshwater and saltwater environments.

What is the intertidal zone?

The zone lying along coastlines between high and low tides.

Where do nutrients primarily come from in deeper waters?

Detritus sinking from more productive surface waters.

What determines global patterns of primary production?

Climate and nutrient availability.

What is a species interaction?

How species affect each other's survival and reproduction, such as competition, mutualism and predation.

Define competition between species.

A species interaction where both species are negatively impacted (-/-), often involving the struggle for limited resources like space and food.

What is competitive exclusion?

When two species with very similar niches cannot coexist, and one outcompetes the other.

What is mutualism?

A species interaction where both species benefit (+/+). An example includes aphids and bacteria.

Define predation.

A species interaction where one species benefits and the other is harmed (+/-), typically where a predator kills and consumes its prey.

Define commensalism.

A species interaction where one species benefits and the other is neither harmed nor helped (+/0).

What is a keystone species?

A species that has a disproportionately large impact on its ecosystem, relative to its abundance.

What is facilitation?

A species interaction where one species makes the environment more suitable for another species.

What is a metapopulation?

A group of spatially separated populations of the same species that interact at some level.

What is population ecology?

The study of how populations of organisms interact with their environment and how population sizes change over time.

What is exponential population growth?

Population growth occurring at a constant rate, leading to a J-shaped curve when plotted on a graph.

What is logistic population growth?

Population growth that slows down as it approaches the carrying capacity of the environment, resulting in an S-shaped curve.

What is carrying capacity?

The maximum population size that an environment can sustain indefinitely given the available resources.

What are density-dependent factors?

Factors that regulate population size and become more intense as population density increases, e.g., competition, disease.

What are density-independent factors?

Factors that regulate population size regardless of population density, e.g., temperature, natural disasters.

What is a cohort?

A group of individuals in a population that are born around the same time.

What is survivorship?

The proportion of individuals that survive to a given age.

What is an ecosystem?

A community of living organisms interacting with their non-living environment.

What is the Anthropocene?

A proposed geological epoch in which humans have become a significant planetary force.

What is assisted migration?

The deliberate transplantation of populations to new locations to help them survive climate change.

What is eutrophication?

The process where a body of water becomes overly enriched with minerals and nutrients, leading to dead zones.

What is an invasive species?

A non-native species that spreads rapidly and causes harm to the environment, economy, or human health.

What is a biological reserve?

An area of land set aside to protect habitats and biodiversity.

What is sustainable development?

Development that meets the needs of the present without compromising future generations.

What are the basic expectations of students and professors in this course?

Students: Arrive on time, print notes, be respectful, don’t use computers. Professors: Start on time, focus on concepts, clarify learning needs, be open to questions.

What is deductive thinking in science?

Advancing hypotheses and comparing them to facts gathered from nature or experiments.

What are the key components of a controlled experiment?

Control groups, replication, and randomization.

What is a hypothesis?

A proposed explanation for a set of facts that can be tested by experiments or observations.

What does it mean to falsify a hypothesis?

To prove a hypothesis false through experimentation or observation.

What is a vestigial trait?

A structure that has no current function but is similar to functional structures in related species.

What is a homology?

A similarity between organisms due to common ancestry.

What are the key assumptions of natural selection?

Heritable variation, differential reproductive success, and non-random selection.

What is fitness in biology?

An organism's ability to survive and reproduce, measured by average reproductive success.

What is acclimation?

An individual's physiological response to changes in environmental conditions.

What are some reasons for a clade to contract?

Changing conditions, competition from other clades, or from a successful member.

What are some key characteristics of primates?

Highly developed stereoscopic vision, versatile limbs, and large brains.

What are hominins?

Humans and our upright ancestors.

What is phylogeny?

The evolutionary history of a group of organisms based on their evolutionary relationships.

What is a monophyletic group (clade or taxon)?

A group defined by a single common ancestor and all of its descendants.

What is a synapomorphy?

A shared, derived trait used as evidence that two or more species are closely related.

What is convergent evolution?

The independent evolution of similar traits in unrelated species.

What is parsimony in phylogenetic analysis?

The principle of choosing the tree that requires the fewest evolutionary changes.

What are the three domains of life?

Bacteria, Archaea, and Eukarya.

What are the biases in the fossil record?

Habitat bias, taxonomic bias, temporal bias, and abundance bias.

What is adaptive radiation?

A rapid diversification of a single lineage into many descendant species with different ecological roles.

What is a mass extinction?

A period of dramatic species loss.

What is a locus?

A location where a gene can occur in a genome.

What is an allele?

A particular version of a gene.

What does it mean to be heterozygous?

Having different alleles at a particular locus.

What does it mean to be homozygous?

Having two copies of the same allele at a particular locus.

What is a genotype?

The collection of an individual's genes.

What is a phenotype?

The collection of an individual's physiological and physical traits that can be observed.

What is the Hardy-Weinberg distribution?

The distribution of genotypes expected if alleles assort randomly and independently.

What is genetic drift?

Change in allele frequencies due to random sampling.

What is gene flow?

The movement of alleles from one population to another.

What is mutation?

Heritable errors in copying DNA that provide variation for natural selection.

What is inbreeding?

Mating between close relatives, leading to more homozygotes and lower survival rates in offspring.

What is sexual selection?

A form of natural selection driven by traits related to success in obtaining mates.

What is directional selection?

Natural selection that shifts the population in a particular direction over time.

What is stabilizing selection?

Natural selection that keeps the population stable, preventing change in a trait.

What is disruptive selection?

Natural selection that favours extreme phenotypes, leading to divergence and speciation.

What is balancing selection?

Natural selection that maintains allele diversity.

What is speciation?

The process by which new species are formed.

What is the biological species concept?

Defines species based on reproductive isolation, meaning members can interbreed successfully within their species.

What is prezygotic isolation?

Mechanisms that prevent successful mating or fertilization.

What is postzygotic isolation?

Mechanisms that prevent offspring from producing offspring of their own.

What is the morphological species concept?

Defines species based on physical differences.

What is the ecological species concept?

Defines species based on their ecological niche.

What is the phylogenetic species concept?

Defines species as a monophyletic group of populations.

What is allopatry?

When organisms live apart from each other.

What is dispersal?

The movement of individuals from one area to another that can result in colonization of new areas.

What is a vicariance event?

A geographic or ecological barrier that splits a population.

What is sympatry?

When organisms live in the same geographic area.

What is reinforcement?

The process where natural selection favours traits that prevent hybridization.

What are hybrid zones?

Areas where the ranges of two species overlap, and they interbreed to some degree.