| A | B |
|---|
| Abiotic components | Nonliving chemical and physical factors in the environment. |
| Abyssal zone | The very deep benthic community near the bottom of the ocean. |
| Aphotic zone | The part of the ocean beneath the photic zone, where light does not penetrate sufficiently for photosynthsis to occur. |
| Benthic zone | The bottom surfaces of aquatic environments. |
| Benthos | The communities of organisms living in the benthic zone of an aquatic biome. |
| Biogeography | The study of the past and present distribution of species. |
| Biome | Major ecosystems that are classified according to the vegetation of organisms. |
| Biosphere | The entire portion of Earth inhabited by life; the sum of all the planet's ecosystems. |
| Biotic components | All the organisms that are part of the environment. |
| Canopy | The uppermost layer of vegetation in a terrestrial biome. |
| Climate | The prevailing weather conditions at a locality. |
| Community | All the organisms that inhabit a particular area |
| Coral Reefs | Warm water, tropical, ecosystems dominated by the hard skeletal structures secreted primarily by the resident cnidarians. |
| Deep-sea hydrothermal vent | A dark, hot, oxygen-deficient environment associated with volcanic activity. |
| Detritus | Dead organic matter. |
| Dispersal | The distribution of individuals within geographic population boundaries. |
| Estuary | The area where a freshwater stream or river merges with the ocean. |
| Eutrophic | Highly productive lake, having a high rate of biological productivity supported by a high rate of nutrient cycling. |
| Intertidal zone | The shallow zone of the ocean where land meets water. |
| Landscape | Terrestrial ecosystems linked by exchanges of energy, materials, and organisms. |
