| A | B |
| ecology | the study of the interactions of living things with one another and with their environment |
| biotic | living factors in the environment |
| abiotic | the nonliving part of the environment, such as water, rocks, light and temperature |
| population | a group of individuals of the same species that are living together |
| community | all of the populations of species that live and interact in an area |
| ecosystem | a community of organisms and their abiotic environment |
| biosphere | the part of the Earth where life exsists |
| producers | organisms that use sunlight to make food |
| consumers | organisms that eat other organisms |
| herbivore | a consumer that eats only plants |
| carnivore | a consumer that eats only animals |
| omnivore | a consumer that eats both plants and animals |
| scavengers | omnivores that eat dead plants and animals |
| decomposers | organisms that get energy from breaking down dead organisms |
| food chain | a diagram that shows how energy in food flows from one organism to another |
| food web | a diagram that shows the feeding relationships between organisms in an ecosystem |
| energy pyramid | a diagram that shows an ecosystem's loss of energy |
| limiting factor | a scarce resource that limits the size of a population |
| carrying capacity | the largest population that an environment can support |
| competition | when two or more organisms try to use the same resource |
| prey | organism that is eaten for energy |
| predator | organism that eats prey |
| camouflauge | blending in with the environment |
| symbiosis | a close, long term association between two or more species |
| mutualism | a symbiotic relationship in which both organisms benefit |
| commensalism | a symbiotic relationship in which one species benefits, and the other is unaffected |
| parasitism | a symbiotic relationship in which one organisms benefits, but the other one is harmed |
| coevolution | when a long term change takes place in two species because of their close interaction with one another |