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the study of living things and their environments


everything that surrounds a living thing


to act upon each other, action between organisms and/or their environment


all populations of different species that live in a certain place


living and nonliving things in an environment, together with their interactions


group of the same kind of organism (same species) living in a certain place at the same time


place where an organism lives


organism's role, or job, in its habitat; what an organism does

carrying capacity

largest amount of a population that can be supported by an area

limiting factors

conditions in the environment that put limits on population size


area where a type of animal or plant population is found


something that happens over and over in the same way; non-ending

nitrogen-fixing bacteria

bacteria that can use nitrogen in the atmosphere to make nitrogen compounds that other organism CAN use


organisms that obtain food by eating other organisms


organism that breaks down the wastes or remains of other organisms


organism that makes its own food using either sunlight energy (photosynthetic) or chemical energy (chemosynthetic)


animal that eats only dead organisms - a type of decomposer

energy pyramid

way of showing how energy moves through a food chain. The same pyramid can show biomass.

food chain

a series or chain of organisms showing feeding relationships. Arrow points to belly of receiver ----> going into the belly

food web

way of showing how food chains are related

climax community

last community in a succession


gradual change in organisms that occurs when the environment changes


large region of the earth with particular plant and animal communities and climate


overall long term weather patterns in an area over a long period of time


wise use of natural resources

natural resource

materials found in nature that are used by living things

nonrenewable resource

materials found in nature that CANNOT be renewed or replaced

renewable resource

natural resouces that CAN be renewed or replaced

endangered species

kinds of living things that are in danger of dying out


release of harmful materials into the environment


thin zone of the earth that supports all life


animal that hunts and eats other animals


animal hunted or caught for food


basic unit of structure and function in living things


any living thing


reaction to a change


trait of a living thing that helps it live in its environment


Everything that surrounds a living thing


process of breaking down food so that it can be used by living things


process of getting rid of wastes


process of taking in food


process of getting energy from food


process of moving nutrients and wastes in a living thing


the ability of a living thing to keep conditions inside its body constant






All the living and non-living things that interect in an area.

Biotic Factors

Living things in an ecosystem or things that were once living

Abiotic Factors

Non-living factors including temperature, water, sunlight, wind, rocks and soil


Any living thing


Taxonomic group whose members can interbreed - reproducting to produce fertile offsprings


A group of organisms of the same species populating a given area


Different populations that live together in a defined area


Places where animals or plants naturally live and grow

Invasive Species

Species that enter new ecosystems and multiply, harming native species and their habitats. Non-native


The relation between two different species of organisms that are interdependent


A close relationship; both species benefit


A close relationship; one species benefits, the other doesn't benefit but isn't harmed


A close relationship; one species benefits, the other is harmed

Potential Niche

The entire range of resource opportunities an organism is potentially able to occupy within an ecostystem

Fundamental Niche

Niche where an organism is actually able to live


Autotrophs convert light energy into chemical energy
CO2 + H2O ---> C6H12O6 + O2


Organism that can make their own food


Organisms that take in food material and are above producers on the energy pyramid


Consumers that eat only plants


Consumers that eat only animals


A consumer that eats both plants and animals


organisms that break down wastes and dead organisms and return raw materials to the environment

Cellular Respiration

Process that releases energy by breaking down food molecules in the presence of oxygen:

Food Chain

A series of steps in which organisms transfer energy by eating and being eaten User-

Food Web

Shows how food chains are related within an ecosystem

Trophic Level

Organism in a food chain that represents a feeding step in the passage of energy and materials through an ecosystem

Carbon Cycle

The organic circulation of carbon from the atmosphere into organisms and back again

Nitrogen Cycle

The cycle in which nitrogen gas is changed into forms of nitrogen that plants can use

Phosphorus Cycle

The process by which phosphorus is recycled in the ecosystem

Ecological Succession

The gradual and orderly process of change in an ecosystem brought about by the progressive replacement of one community by another until a stable climax is established

Primary Succession

The series of changes that occur in an area where no ecosystem previously existed - Starts on bare rock

Secondary Succession

The series of changes that occur after a disturbance of an existing ecosystem - Starts on Soil

Pioneer Species

The first species to live in an area of primary succession; usually lichens (alice algae lichen freedy fungus)

Climax Community

A stable, mature community that undergoes little or no change in species over time.

Growth Rate

Rate of increase or decrease of a population

Generation Time

Average time between one generation of offspring and the next

Exponential Growth

Occurs when the individuals in a population reproduce at a constant rate

Carrying Capacity

Largest number of individuals of a population that a environment can support


Interaction in which two or more species use the same limited resource

Limiting Resource

A short supply of resources restricting the growth of a population

Reproductive Potential

Rate at which a specices can increase population


Cold and largely treeless across northern North America


Permanently frozen layer of soil under the surface

Tropical Forest

Near the equator

Temperate Forest

Distinct seasons and moderate climate

Temperate Deciduous Forest

Trees lose their leaves in fall and regrow in spring


A forested biome dominated by coniferous trees


Prairies, steppes, pampas, veldts; near the equator, characterized by treeless areas and tall grasses.


Rainfall less than 9.9 inches per year

Primary succession

A series of organisms changing their environment that starts on BARE rock.

Secondary succession

A series of organisms changing their environment that starts on soil.


Occurs when a toxic pollutant that is not excreted accumulation in the body and appears in highist concentration at the top of the food chain. It's pyramid is upside down.


All the water on our plant: lakes, oceans, rivers, groundwater, st

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