Vocabulary Review Ecology

The study of the interactions between organisms and the other living and nonliving components of their environment Ecology

The dependence of every organism on its connections with other living and nonliving parts of its environment Interdependence

A model that represents or describes the relationships between the components of an ecological system Ecological model

The part of the Earth where life exists; includes all of the living organisms on Earth Biosphere

A community of organisms and their abiotic environment Ecosystem

A group of various species that live in the same habitat and interact with each other Community

A group of organisms of the same species that live in a specific geographical area and interbreed Population

The place where an organism usually lives Habitat

An environmental factor that is associated with or results from the activities of living organisms Biotic factor

An environmental factor that is not associated with the activities of living organisms Abiotic factor

A graph of the performance of an organism versus the value of an environmental variable Tolerance curve

An organism’s change in response to a change in the organism’s environment Acclimation

A state in which seeds, spores, bulbs, and other reproductive organs stop growth and development and reduce their metabolism, especially respiration Dormancy

In general, any movement of individuals or populations from one location to another; specifically, a periodic group movement that is characteristic of a given population or species Migration

The unique position occupied by a species, both in terms of its physical use of its habitat and its function within an ecological community Niche

An organism that can make organic molecules from inorganic molecules; a photosynthetic or chemosynthetic autotroph that serves as the basic food source in an ecosystem Producer

The production of carbohydrates through the use of energy from inorganic molecules instead of light Chemosynthesis

The rate at which organic matter is assimilated by plants and other producers during a period of time over a certain area Gross primary productivity

Any organic material that has been produced in an ecosystem Biomass

Each step in a food chain or food web; first level is producers, then consumers, which make up second, third, and higher levels Trophic Level

A diagram that shows the relative amounts of energy or matter contained within each trophic level in a food chain or web; 3 types: energy, biomass, and pyramids of numbers\ Ecological Pyramid

The rate at which biomass accumulates in an ecosystem Net primary productivity

An organism that eats other organisms or organic matter instead of producing its own nutrients or obtaining nutrients from inorganic sources Consumer

An organism that eats only plants Herbivore

An organism that eats animals Carnivore

An organism that eats a variety of other organisms, including animals and plants Omnivore

A consumer that feeds on dead organisms or on the parts of wastes of other organisms Detritivore

An organism that feeds by breaking down organic matter from dead organisms; examples include bacteria and fungi Decomposer

An organism’s relative position in a sequence of energy transfers in a food chain or food pyramid, examples include producers and primary, secondary, and teriary consumers Trophic level

The pathway of energy transfer through various stages as a result of the feeding patterns of a series of organisms Food chain

A diagram that shows the feeding relationships among organisms in an ecosystem Food web

Cycle the circulation of substances through living organisms from or to the environment Biogeochemical cycle

Any relationship in which two species live closely together Symbiosis

Both species benefit from the relationship Mutualism

One member of the relationship benefits and the other is neither helped nor harmed Commensalism

One orgasm lives on or inside another organism and harms it Parasitism

The water that is beneath the Earth’s surface Groundwater

The continuous movement of water between the atmosphere, the land, and the oceans Water Cycle

The process by which plants release water vapor into the air through stomata; also, the release of water vapor into the air by other organisms Transpiration

The movement of carbon from the nonliving environment into living things and back Carbon cycle

The process in which nitrogen circulates among the air, soil, water, plants, and animals in an ecosystem Nitrogen cycle

The process by which gaseous nitrogen is converted into nitrates, compounds that organisms can use to make amino acids and other nitrogen- containing organic molecules Nitrogen fixation

A bacterium that converts atmospheric nitrogen into ammonia Nitrogen-fixing bacteria

The formation of ammonia compounds in the soil by the action of bacteria on decaying matter Ammonification

The process by which nitrites and nitrates are produced by bacteria in the soil Nitrification

The liberation of nitrogen from nitrogen-containing compounds by bacteria in the soil Denitrification

The cyclic movement of phosphorus in different chemical forms from the environment to organisms and then back to the environment Phosphorus cycle