Advertisement Upgrade to remove ads

ecology

scientific study of interactions among organisms and between organisms and their environment

organism

an individual living thing

population

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

community

all of the populations in an ecosystem

ecosystem

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

biosphere

part of Earth in which life exists including land, water, and air or atmosphere

lithosphere

the solid part of the earth consisting of the crust and outer mantle

hydrosphere

all the water at and near the surface of the earth, 97% of which is in oceans

atmosphere

the mass of air surrounding the Earth

biotic

of or relating to living organisms

abiotic

any nonliving component of an environment

limiting factor

anything that restricts the number of individuals in a population

biome

a major biotic community characterized by the dominant forms of plant life and the prevailing climate

tundra

a vast, level, treeless plain in the arctic regions. The ground beneath the surface of the tundras is frozen even in summer

savanna

a flat grassland in tropical or subtropical regions

temperate deciduous forest

forest in a temperate region, characterized by trees that drop their leaves annually

grasslands

A biome dominated by grasses and associated herbaceous plants

desert

A type of biome characterized by low moisture levels and infrequent and unpredictable precipitation. Daily and seasonal temperatures fluctuate widely

tropical rain forest

biome near the equator with consistant warm temperatures, wet weather, and lush plant growth

coniferous forest

forest populated by cone-bearing evergreen trees; mostly found in northern latitudes

chaparral

Thick, dense, thorny evergreen shrub found in Mediterranean climates

aquatic

pertaining to water

population density

number of individuals per unit area

carrying capacity

largest number of individuals of a population that a given environment can support

predator

animal that hunts and eats other animals

prey

animal hunted or caught for food

competition

the struggle between organisms to survive in a habitat with limited resources

habitat

the type of environment in which an organism or group normally lives

niche

organism's role, or job, in its habitat

symbiotic relationship

an interaction between two or more species that live together in direct contact

parasitism

symbiotic relationship in which one organism lives in or on another organism (the host) and consequently harms it

mutualism

symbiotic relationship in which both species benefit from the relationship

commensalism

symbiotic relationship in which one member of the association benefits and the other is neither helped nor harmed

ecological succession

(ecology) 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

pioneer organism

the first organisms in an ecological succession that work the land

lichen

Symbiotic association between a fungus and a photosynthetic organism

climax community

a relatively stable long-lasting community reached in a successional series

primary succession

the series of changes that occur in an area where no soil exists

secondary succession

ecological succession following a disturbance that destroys a community without destroying the soil

autotroph

an organism that makes its own food; also called a producer

phototroph

an organism that gets its energy from sunlight

chemotroph

an organism that gets its energy from chemicals taken from the environment

heterotroph

organism that obtains energy from the foods it consumes; also called a consumer

herbivore

organism that obtains energy by eating only plants

carnivore

organism that obtains energy by eating animals

scavenger

any animal that feeds on dead animals

omnivore

a consumer that eats both plants and animals

decomposer

an organism that gets energy by breaking down the remains of dead organisms or animal wastes and consuming or absorbing the nutrients

food chain

series of steps in an ecosystem in which organisms transfer energy by eating and being eaten

food web

network of complex interactions formed by the feeding relationships among the various organisms in an ecosystem

producer

an organism that makes its own food; also called an autotroph

primary consumer

An organism that eats producers

secondary consumer

An organism that eats primary consumers

tertiary consumer

An organism that eats secondary consumers

pyramid of energy

an ecological pyramid that shows the energy flow through each trophic level in an ecosystem.

trophic level

feeding level in an ecosystem

water cycle

the continuous process by which water moves from Earth's surface to the atmosphere and back

carbon oxygen cycle

The movement of carbon and oxygen through the environment. Involves respiration, photosynthesis, decomposition, burning of oxygen, and plants and animals.

nitrogen cycle

the transfer of nitrogen from the atmosphere to the soil, to living organisms, and back to the atmosphere

renewable resources

resources that can be replaced in a relatively short period of time (food, solar energy, oxygen)

nonrenewable resources

resources that cannot be replaced in a short amount of time, people will use them up before they can be replaced by nature (fossil fuels, minerals, old growth forests)

Three R's

Reduce, reuse, recycle

deforestation

The process of stripping the land of its trees

greenhouse effect

natural situation in which heat is retained in Earth's atmosphere by carbon dioxide, methane, water vapor, and other gases

global warming

An increase in the average temperature of the earth's atmosphere (especially a sustained increase that causes climatic changes)

acid rain

rain containing acids that form in the atmosphere when industrial gas emissions (especially sulfur dioxide and nitrogen oxides) combine with water

pollution

Release of harmful materials into the environment

biological magnification

process by which pollutants become more concentrated in successive trophic levels of a food web

ozone depletion

caused by CFCs, methyl chloroform, carbon tetrachloride, halon, methyl bromide all of which attack stratospheric ozone. Negative effects of ozone depletion include increased UV, skin cancer, cataracts, and decreased plant growth.

biodiversity

the diversity of plant and animal life in a particular habitat (or in the world as a whole)

invasive species

species that enter new ecosystems and multiply, harming native species and their habitats

overexploitation

practice of harvesting or hunting to such a degree that remaining individuals may not be able to replenish the population

conservation

the preservation and careful management of the environment and of natural resources

thermal pollution

harm to lakes and rivers resulting from the release of excessive waste heat into them

smog

air pollution by a mixture of smoke and fog, it makes a grey/brown haze

erosion

The process by which wind, water, ice, or gravity transports soil and sediment from one location to another

trade-off

alternatives that must be given up when one is chosen over another

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again

Example:

Reload the page to try again!

Reload

Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording

Create Set