| A | B |
|---|
| organism | a living thing |
| habitat | an enviromnent that provides the things a specific organism nees to live, gorw, and reproduce |
| biotic factor | the parts of a habitat that are living, or once living, and interact with an organism |
| abiotic factor | nonliving parts of an organisms habitat |
| species | a group of organisms that can mate with each other and produce offspring that can also mate and reproduce |
| population | all the members of one species living in a particular area |
| community | all the different populations that live together in an area |
| ecosystem | the community of organisms that live in a particular area, along with their non-living environment |
| ecology | the study of how organisms interact with each other and with their environment |
| birth rate | the number of births per 1000 individuals for a given time period |
| death rate | the number of deaths per 1000 individuals for a given time period |
| immigration | moving into a population |
| emigration | moving out of a population |
| population density | the number of individuals in an area of a specific size |
| limiting factor | an environmental factor that causes a population to stop growing or decrease |
| carrying capacity | the largest population that an area can support |
| natural selection | when a characteristic that makes an individual better suited to a specific environment become common |
| adaption | the behaviors and physical characteristics that allow organisms to live successful in their environment |
| niche | the role of an organism in its environment |
| competition | the struggle between organisms to survive as they attempt to use the same limited resources |
| predation | an interaction in which one organism kills another for food or nutrients |
| predator | the organism that does the killing |
| prey | the organism that is killed |
| symbiosis | a relationship in which two species live closely together and at least one species benefits |
| mutualism | both species benifit |
| commensalism | one species benefits and the other species is neither helped or harmed |
| parasitism | a relationship that involves on organism living with, on, or inside another organism and harming it |
| parasite | the organism that benefits from parasitism |
| host | the organism that a parasite lives on or in |
