| A | B |
|---|
| prey | an organism that is eaten by a predator |
| innate behavior | a behavior that is natural for an organism and does not need to be learned |
| population density | the number of individuals in an area that is calculated by dividing the number of organisms by the size of the area |
| symbiosis | a relationship between species in which at least one member benefits is called what |
| predator | an animal that obtains its food by killing and eating other organisms |
| limiting factor | availability of food, water, and living space, and the spread of disease are examples of this |
| commensalism | a symbiotic relationship in which one organism benefits and the other is unaffected |
| mutualism | a sybiotic relationship in which both organisms benefit |
| parasitism | a symbiotic relationshipin which one organism beefits and the other is harmed |
| ecology | the study of living things |
| competition | when two or more species in an ecosystem must use the same limited resources and compete for them with each other |
