| A | B |
|---|
| Population | Individuals of one species living in one area |
| Community | All the organisms living in one area |
| Ecosystem | All the organisms in a given area as well as the abiotic factors with which they interact |
| Biosphere | The global ecosystem |
| Biotic factors | Living things |
| Abiotic factors | Nonliving and physical factors |
| Dispersion | Pattern of spacing of individuals within the area the population inhabits |
| Food Chain | Pathway along which energy is transferred from one trophic level to another |
| Density dependent factors | Increase directly as the population increases |
| Density independent factors | Unrelated to population density |
| Carrying capacity | Number of individuals that can occupy one area at a particular time |
| Biomes | Major ecosystems of Earth classified by predominant vegetation |
| Ecological niche | Nutritional role in an ecosystem |
| Mutualism | Both organisms benefit |
| Commensalism | One benefits and one remains unaffected |
| Parasitism | One benefits while the other is harmed |
| Biotic potential | Maximum rate at which a population could increase under ideal conditions; influenced by different factors |
