| Term | Definition |
| Producer | An organism that can produce its own food |
| Consumer | An organism that relies on other organisms for food |
| Predation | A predator-prey relationship |
| Mutualism | A relationship that benefits both organisms |
| Commensalism | A relationship where one organism benefits and the other is uneffected |
| Parasitism | A relationship where one organism benefits at the cost of another |
| Herbivore | An organism that eats only producers |
| Omnivore | An organism that eats both producers and consumers |
| Carnivore | An organism that eats other consumers |
| Trophic level | A level in a food chain |
| Food chain | The interactions between organisms in an environment |
| Food web | The interactions between a specific group of organisms |
| An example of mutualism | Black Garden Ants and Aphids |
| An example of commensalism | Red-winged blackbird and purple loosestrife |
| An example of parasitism | Wasp and Monarch |