IB ESS Topic 2 Flashcards

Flashcards for IB ESS Topic 2, covering ecosystems and ecology.

The __ is an ecological system composed of individuals, populations, communities, ecosystems.

biosphere

A __ is a group of organisms that can interbreed and produce fertile offspring.

species

__ use a variety of tools to identify an organism, including dichotomous keys and DNA surveys.

Taxonomists

A __ is a group of organisms of the same species who live in the same area at the same time, and which are capable of interbreeding.

population

__ refers to the living components of an ecosystem.

Biotic

__ refers to non-living physical factors that may influence organisms.

Abiotic

A __ describes the particular set of abiotic and biotic conditions and resources to which an organism or population responds.

niche

__ competition is between the same species.

Intraspecific

__ competition is between different species for the same resource.

Interspecific

__: Primary consumers feed only on plants.

Herbivory

__: A consumer eats and kills another consumer.

Predation

__: An organism that lives entirely on or in a host species and cannot survive without it.

Parasitism

__: Two organisms co-exist and benefit each other forming a relationship.

Mutualistic

__ is the maximum size of a population determined by competition for limited resources.

Carrying capacity

J curves show a __ pattern, with growing exponentially at first and suddenly collapsing.

boom and bust

__ occur when populations overshoot the carrying capacity.

Diebacks

Methods for estimating the abundance of non-motile organisms include the use of __ for making actual counts.

quadrats

__ random sampling is used when there is an obvious difference within an area to be sampled and two or more sets of samples are taken.

Stratified

A __ is a continuous sample path/line/strip along which you record the occurrence and/or distribution of plants and animals in a particular study area.

transect

The __ is used to estimate the population of animal species in a given area at a given time, using mark and recapture.

Lincoln Index

A __ is a collection of interacting populations within the ecosystem.

community

__ is the location in which a community, species, population or organism lives.

Habitat

__ are open systems in which both energy and matter can enter and exit.

Ecosystems

__ is a natural property of ecosystems where inputs are balanced by outputs.

Sustainability

__ species have a disproportionate impact on community structure and the risk of ecosystem collapse if they are removed.

Keystone

The first law of __ states that as energy flows through ecosystems, it can be transformed from one form to another but cannot be created or destroyed.

thermodynamics

__ is the conversion of light energy to chemical energy in the form of glucose, some of which can be stored as biomass by autotrophs.

Photosynthesis

__ releases energy from glucose by converting it into a chemical form that can easily be used in carrying out active processes within living cells.

Cellular respiration

The second law of __ states that energy transformations in ecosystems are inefficient.

thermodynamics

__ gain chemical energy from carbon (organic) compounds obtained from other organisms.

Consumers

In a food chain, organic matter flows from primary producers to primary consumers to __ consumers, and so on.

secondary

The conversion of energy into biomass for a given period of time is measured as __.

productivity

__ productivity (GP) is the total gain in biomass by an organism.

Gross

__ productivity (NP) is the amount remaining after losses due to cellular respiration.

Net

Food __ show the complexity of trophic relationships in communities.

webs

Methods for estimating the __ and energy of trophic levels in a community include measurement of dry mass, controlled combustion and extrapolation from samples.

biomass

__ refers to the increasing concentration of non-biodegradable pollutants in organisms or trophic levels over time.

Bioaccumulation

__ refers to the increasing concentration of non-biodegradable pollutants along a food chain.

Biomagnification

__ cycles ensure chemical elements continue to be available to living organisms.

Biogeochemical

indicate net accumulation of the element; whereas _ indicate net release of the element.

Sinks, Sources

The __ cycle contains storages (sometimes referred to as sinks and sources) and flows, which move matter between storages.

carbon

__ agricultural methods, such as crop rotation, cover crops and no till, will promote the role of soil as a carbon sink.

Regenerative

While oceans act as a carbon __, the human use of fossil fuels releases inorganic carbon at a faster rate than oceans can absorb it.

sink

A __ is a group comparable ecosystems that have developed similar climatic conditions, wherever they occur.

biome

and _ are major influences on the distribution of terrestrial biomes.

Insolation, temperature

__ refers to changes in community along an environmental gradient.

Zonation

Transects can be used to measure _ and ___ factors along an environmental gradient in order to determine the variables that affect the distribution of species.

biotic, abiotic

__ diagrams show the distribution of a species (frequency or percentage coverage) of species along an environmental gradient.

Kite

__ is the replacement of one community by another in an area over time, due to changes in biotic and abiotic variables.

Succession

Each __ community (sere) in a succession causes changes in the environmental conditions that allow the next community to replace it through competition until a stable climax community is reached.

seral

__ succession occurs on newly formed substratum where there is no soil or pre-existing community, such as rock newly formed by volcanism.

Primary

__ successions happen on bare soil where there has been a pre-existing community, such as a field where agriculture has ceased.

Secondary

Communities are affected by __ such as flood, fire, landslides, earthquakes, hurricanes and other natural hazards.

disturbance