| A | B |
|---|
| community | a group of various species that live in the same habitat and interact with each other |
| ecosystem | a community of organisms and their abiotic environment |
| habitat | the place where an organism usually lives |
| biodiversity | the variety of organisms in a given area |
| succession | the replacement of one type of community by another at a single location over a period of time |
| climate | average weather conditions in an area over a long period of time |
| biome | a large region characterized by a specific type of climate and certain types of plant and animal communities |
| producer | 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 |
| consumer | an organism that eats other organisms or organic matter instead of producing its own nutrients or obtaining nutrients from inorganic sources |
| decomposer | an organism that feeds by breaking down organic matter from dead organisms; examples include bacteria and fungi |
| energy pyramid | a triangular diagram that shows an ecosystem's loss of energy |
| carbon cycle | the movement of carbon from the nonliving environment into living things and back |
| respiration | in biology |
| nitrogen cycle | the cycling of nitrogen between organisms |
| Phosphorus cycle | the cyclic movement of phosphorus in different chemical forms from the environment to organisms and then back to the environment |
| population | a group of organisms of the same species that live in a specific geographical area |
| carrying capacity | the largest population that an environment can support at any given time |
| predation | an interaction between two organisms in which one organism |
| coevolution | the evolution of two or more species that is due to mutual influence |
| parasitism | a relationship between two species in which one species |
| symbiosis | a relationship in which two different organisms live in close association with each other |
| mutualism | a relationship between two species in which both species benefit |
| commensalism | a relationship between two organisms in which one organism benefits and the other is unaffected |
| niche | the unique position occupied by a species |
| fundamental niche | the largest ecological niche where an organism or species can live without competition |
| realized niche | the range of resources that a species uses |
| competitive exclusion | the exclusion of one species by another due to competition |
| keystone species | a species that is critical to the functioning of the ecosystem in which it lives because it affects the survival and abundance of many other species in its community |
| fossil fuel | a nonrenewable energy resource formed from the remains of organisms that lived long ago; examples include oil |
| acid rain | precipitation that has a pH below normal and has an unusually high concentration of sulfuric or nitric acids |
| global warming | a gradual increase in average global temperature |
| greenhouse effect | the warming of the surface and lower atmosphere of Earth that occurs when carbon dioxide |
| erosion | a process in which the materials of Earth's surface are loosened |
| deforestation | the process of clearing forests |
| biodiversity | the variety of organisms in a given area |
| extinction | the death of every member of a species |
| recycling | the process of recovering valuable or useful materials from waste or scrap; the process of reusing some items |
| ecotourism | a form of tourism that supports the conservation and sustainable development of ecologically unique areas |
