Chapter 15

Carrying capacity

Ability of an ecosystem to support biodiversity

Stability

Ability of an ecosystem to withstand and recover from changes

Decomposer

Bacterium or fungus that feeds on detritus by secreting enzymes that break it down into simpler molecules

Scavenger

Carnivore that does not kill its own food but feedstock i'm dead animals instead

Trophic level

Classification that describes an organism's feeding relationship to other organisms in its exosystem; step in a food chain

Symbiosis

Close relationship between two different species over a period of time, especially one in which they mutually benefit

Biogrochemical cycle

Cycle that recycles nutrients in the environment; also called nutrient cycle

Pioneer species

First organisms to colonize an ecosystem after a disturbance

Niche

Function or "occupation" of a living thing

Habitat

Region where a particular organism normally lives; the organism's environment or home

Biosphere

Relatively thin layer of the earth's surface in which life exists

Ecological succession

Replacement of early pioneer species in a disturbed ecosystem by later species in an orderly progression until the climax community is established

Climax vegetation

Species of plants theater dominate a region and characterize a biome

Ecology

Study of how living things interact with one another and with their physical environment

Mutualism

Symbiotic relationship in which both organisms benefit

Parasitism

Symbiotic relationship in which one organism benefits while the other is harmed

Limiting factor

Environmental factor outside an organism's tolerances range

Food web

Model that combines food chains to show all possible feeding relationships at each trophic level

Nonrenewable resource

Natural resource that regenerates slowly, if at all

Renewable resource

Natural resource that regenerates very quickly

Biodiversity

Number and variety of species living within an ecosystem

Heterotroph

Organism that cannot produce Iran own food and must obtain energy from organic sources; also called a consumer

Detrivore

Organism that feeds on detritus but cannot actually convert the detritus into a soil component

Autotroph

Organism that makes Iran own food using an inorganic energy source; also called a producer

Permafrost

Permanently frozen layer of soil 2 to 3 feet below the surface, found in Arctic Tundra