IB Biology - Ecology Vocabulary

Flashcards covering essential vocabulary from IB Biology Ecology Learning Targets.

Species

Groups of organisms with shared traits, according to the original morphological concept.

Population

Interacting groups of organisms of the same species living in an area.

Reproductive Isolation

Used to distinguish one population of a species from another.

Community

All of the interacting organisms in an ecosystem, including plants, animals, fungi, and bacteria.

Biological Species Concept

A group of organisms that can breed and produce fertile offspring.

Binomial System

A system for naming organisms where the first part identifies the genus and the second part distinguishes the species.

Habitat

The place in which a community, species, population, or organism lives, including geographical, physical locations, and ecosystem type.

Abiotic

Non-living variables affecting species distribution, influencing a species' range of tolerance.

Biotic

Living variables affecting species distribution

Range of Tolerance

The range of environmental conditions within which a species can survive and reproduce.

Biome

Groups of ecosystems with similar communities due to similar abiotic conditions and convergent evolution.

Ecological Niche

The role of a species in an ecosystem, including biotic and abiotic interactions influencing growth, survival, and reproduction.

Fundamental Niche

The potential niche of a species based on its adaptations and tolerance limits.

Realized Niche

The actual extent of a species' niche when in competition with other species.

Competitive Exclusion

When two species compete, the elimination of one of the competing species or the restriction of both to a part of their fundamental niche.

Autotrophs

Organisms that use external energy sources to synthesize carbon compounds from simple inorganic substances.

Photoautotrophs

Use light as the external energy source.

Chemoautotrophs

Use oxidation reactions as the energy source.

Archaea

One of the three domains of life and appreciate that they are metabolically very diverse; species use either light, oxidation of inorganic chemicals or oxidation of carbon compounds to provide energy for ATP production

Heterotrophs

Organisms that use carbon compounds obtained from other organisms to synthesize the carbon compounds that they require.

Holozoic nutrition

Food is ingested, digested internally, absorbed and assimilated.

Mixotrophic nutrition

A protist that is both autotrophic and heterotrophic

Saprotrophic nutrition

Fungi and bacteria with this mode of heterotrophic nutrition can be referred to as decomposers.

Decomposers

Fungi and bacteria with this mode of heterotrophic nutrition.

Producer

Organisms that synthesizes its own food from inorganic substances

Primary Consumer

An organism that feeds on producers; an herbivore.

Secondary Consumer

An organism that eats primary consumers; a carnivore.

Tertiary Consumer

An organism that eats secondary consumers; a carnivore.

Food Chain/Web

Diagram shows the transfer of energy from one organism to another

Energy Pyramid

A graphical representation designed to show the biomass or bio productivity at each trophic level in a given ecosystem.

obligate anaerobes, facultative anaerobes and obligate aerobes

Organisms whose tolerance is limited to the presence or absence of oxygen gas in their environment.

Carbon Cycle

How carbon is recycled in ecosystems by photosynthesis, feeding and respiration.

Primary Production

Accumulation of carbon compounds in biomass by autotrophs

Secondary Production

Accumulation of carbon compounds in biomass by heterotrophs

Carbon Sinks

Ecosystems that have a net uptake of carbon dioxide

Carbon Sources

Ecosystems that have a net release of carbon dioxide

Keeling Curve

A graph of the accumulation of carbon dioxide in the atmosphere based on continuous measurements taken at the Mauna Loa Observatory on the island of Hawaii from 1958 to the present; shows annual fluctuations and the long-term trend.

Population Size

The number of individuals in a population.

Random Sampling

Estimating population size, rather than counting every individual, and the need for randomness in sampling procedures.

Random Quadrat Sampling

Used to estimate population size for sessile organisms

Sessile

Not moving; permanently attached or fixed.

Capture–mark–release–recapture

Used to estimate population size for motile organisms.

Lincoln index

Population size estimate = M × (N/R), where M is the number of individuals caught and marked initially, N is the total number of individuals recaptured and R is the number of marked individuals recaptured.

Motile

Capable of motion.

Carrying Capacity

A simple definition is sufficient, with some examples of resources that may limit carrying capacity.

Density-dependent

Numbers of individuals in a population may fluctuate due to density-independent factors, but density-dependent factors tend to push the population back towards the carrying capacity.

Density-independent

Numbers of individuals in a population may fluctuate due to density-independent factors

Population growth curves/Sigmoid population growth curve

Reasons for exponential growth in the initial phases. A lag phase is not expected as a part of sigmoid population growth.

Cooperation/Intraspecific

Reasons for intraspecific competition within a population. Also include a range of real examples of competition and cooperation.

Endemic

(of a plant or animal) native or restricted to a certain place

Invasive

Introduced spieces

Herbivory

An animal that feeds on plants

Predation

An animal that feeds on on other animlas

Mutualism

Interspecific relationship that benefits both species.

Parasitism

An organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense.

Pathogenicity

The ability of an organism to cause disease

Mutualism

An organism that lives in or on another organism (its host) and benefits by deriving nutrients at the host's expense.

Top down and bottom up control

Both of these types of control are possible, but one or the other is likely to be dominant in a community.

Allelopathy

A chemical substance is released into the environment to deter potential competitors.

Stability

Evidence of forest, desert or other ecosystems that have shown continuity over long periods.

Ecosystem

Property of natural ecosystems.

Keystone species

The disproportionate impact on community structure of keystone species and the risk of ecosystem collapse if they are removed.

Eutrophication

Resulting from leaching of nitrogen and phosphate fertilizers, including increased biochemical oxygen demand (BOD).

Pollutants

DDT and mercury, toxin that accumulate in the tissues of consumers in higher trophic levels.

Microplastic

Small pieces of plastic that accumulate in the ocean

Macroplastic

Large pieces of plastic that accumulate in the ocean

Anthropogenic

Related to, or resulting from the influence of humans

Climate Change

A long-term change in the average weather patterns that have come to define Earth’s local, regional and global climates

Positive Feedback

Enhances or amplifies changes; release of carbon dioxide from deep ocean, increases in absorption of solar radiation due to loss of reflective snow and ice, accelerating rates of decomposition of peat and previously undecomposed organic matter in permafrost, release of methane from melting permafrost and increases in droughts and forest fires

Negative Feedback

Tends to minimize changes

Upwelling

Warmer surface water can prevent nutrient upwelling to the surface, decreasing ocean primary production and energy flow through marine food chains.

Afforestation

The establishment of a forest or stand of trees in an area where there was previously no forest.

Forest Regeneration

A type of natural regeneration in which seedlings or saplings that develop or are planted originate within a forest stand

Peat Formation

Occurs in waterlogged soils in temperate and boreal zones and also very rapidly in some tropical ecosystems.

Biodiversity

The variety of life in all its forms, levels and combinations

Anthropogenic species

Extinction caused by humans rather than of non-anthropogenic causes of previous mass extinctions.

Ex situ

Zoos and botanic gardens and storage of germplasm in seed or tissue banks

EDGE program

Selection of evolutionarily distinct and globally endangered species for conservation prioritization.