| Term | Definition |
| Organism | A living thing |
| Species | a type of living thing that is completely different from all others |
| population | a group of organisms of the same speices |
| community | all the living things in an area |
| environment | all the non-living things in an area |
| Biotic | living |
| abiotic | non-living |
| niche | the organisms job or role |
| competition | organisms struggle to get resources |
| resources | food, shelter, water and mates |
| interdependancy | organisms rely on each other |
| material cycle | materials are used over and over again |
| ecosystem | all the biotic and abiotic factors |
| succession | changes in an environment over a long time |
| primary succession | changes that start on bare rock |
| secondary succession | changes in an environment after a natural disaster such as a flood or a fire |
| food chain | shows how energy flows from producer through top carnivore |
| food web | al the feeding relationships in a community |
| predator | the hunter |
| prey | the hunted |
| parasite | an organism that hurts another organism without killing it |
| host | what a parasite feeds on |
| mutualism | when two different species work together - both are helped |
| commensalism | when two different species work together - one is help the other is not affected |
| parasitism | when two species work together - one is helped and one is harmed |
| producer | a plant (autotroph) |
| consumer | an animal (heterotroph) |
| autotroph | an organism that makes its own food (producer) |
| heterotroph | an organism that must eat other organisms (consumer) |
| herbivore | eats only plants |
| carnivore | eats only animals |
| omnivore | eats both plants and animals |
| biodiversity | the variety of life forms |
| decomposer | an organism that breaks down materials and recycles them |
| scavenger | a consumer that eats dead animals |
| precipitation | rain, snow or sleet |
| evaporation | when water changes into water vapor |
| condensation | when water vapor changes into water |
| Habitat | where an organism lives |
| photosynthesis | when plants use the suns energy to make food |