| A | B |
|---|
| Abiotic | nonliving part of an ecosystem |
| Biotic | living or once-living things in an ecosystem |
| Community | all the populations living in the same area at the same time |
| Ecosystem | all the living things and nonliving things in a given area |
| Habitat | place within an ecosystem that provides food, water, shelter, and other biotic and abiotic factors an organism needs to survive and reproduce |
| Population | all the organisms of the same species that live in the same area at the same time |
| Niche | way a species interacts with abiotic and biotic factors to obtain food, find shelter, and fulfill other needs |
| Overpopulation | when a population becomes so large that it causes damage to the environment |
| Competition | demand for resources, such as food, water, and shelter, in short supply in a community |
| Predation | act of one organism, a predator, feeding on another organism, its prey |
| Symbiosis | lose, long-term relationship between two species that usually involves an exchange of food or energy |
| Producers | organism that uses an outside energy source, such as the Sun, and produces its own food |
| Consumers | organism that cannot make its own food; obtains food by eating producers or other consumers |
| Food web | model of energy transfer that can show how the food chains in a community are interconnected |
