Ecology Vocabulary Review Get out vocab sheet. Ecology: The study of how living things interact with nature Ecosystems • The study of how living things interact with nature Abiotic Non Living parts of the environment Biotic The living parts of the environment Symbiosis A relationship where two different species live closely and interact often. Mutualism A type of symbiosis is when two species help each other. Commensalism A type of symbiosis when one species benefits from another but the second species isn’t affected Parasitism A type of relationship where one organism benefits while harming the other organism. Carrying Capacity The maximum number of organisms of a species an ecosystem can hold Limiting Factor The scarcest resource or the one that runs out first that causes a population to decline. Adaptation A trait that helps an organism survive. Predator An organism that hunts others for food Prey An organism that is hunted for food Coevolution When a relationship between two species causes them both to adapt. Population All of the members of a species in an area Ecosystem A community of organisms and their environment. Biosphere All of the living space on earth. Community All of the different organisms of different groups in an area Competition When two organisms fight over the same resources