| Biotic | Describes living factors in the environment |
| Abiotic | Describes the nonliving part of the environment, including water, rocks, light, and temperature. |
| Ecology | The study of the interactions of living organisms with one another and with their environment. |
| Population | A group of organisms that are closely related and can mate to produce fertile offspring. |
| Community | All the populations of species that live in the same habitat and interact with each other |
| Ecosystem | a community of organisms and their abiotic environment |
| Biosphere | The part of the Earth where life exists |
| Producer | Organisms that use sunlight directly to make food |
| Consumer | Organisms that eat other organisms |
| Herbivore | An organism that only eats plants |
| Carnivore | An organisms that eats only animals |
| Omnivore | An organims that eats both plants and animals |
| Scavenger | Omnivores that eat dead plants and animals |
| Decomposer | Organisms that get energy by breaking down dead organisms |
| Food chain | the pathway of energy transfer through various stages as a result of feeding patterns of a series of organisms |
| Food web | A diagram that shows the feeding relationships between organisms in an ecosystem |
| Energy Pyramid | A triangular diagram that shows an ecosystem's loss of energy, which results as energy passes through the ecosystem's food chain. |
| Carrying Capacity | The larges population that an environment can support at any given time |
| Competition | When two or more individuals or populations try to use the same resource, such as food, water, shelter, space, or sunlight |
| Prey | An organism that is killed or eaten by another organism |
| Predator | An organism that kills and eats all or part of another organism |
| Symbiosis | A relationship in which two different organisms live in close association with each other |
| Mutalism | 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. |
| Parasitism | A relationship between two species in which one species, the parasite, benefits from the other species, the host, which is harmed. |
| Coevolution | The evolution of two species that is due to mutual influence, often in a way that makes the relationship more beneficial to both species. |