| A | B |
|---|
| ecosystem | all the living and nonliving things that interact in a particular area |
| habitat | the place where an organism lives |
| biotic factors | the living parts of an ecosystem |
| abiotic factors | the nonliving parts of an ecosystem |
| photosynthesis | the process by which producers make food from sunlight, water, and carbon dioxide |
| species | a group of organisms that are physically similar and can reproduce with each other |
| population | all members of one species in a particular area |
| organism | the smallest unit of organization in an ecosystem |
| community | all the different populations in a particular area |
| ecology | the study of how living things interact with each other and with their environment |
| natural selection | the process by which populations become better suited to their environment |
| adaptations | the behaviors and physical characteristics of species that allow them to live successfully in their environment |
| niche | an organism's particular role in an ecosystem |
| competition | the struggle between organisms to survive in a habitat with limited resources |
| predation | an interaction in which one organism kills and eats another |
| predator | the organism that does the killing |
| prey | the organism that is killed |
| symbiosis | a close relationship between two species that benefits at least one of the species |
| mutualism | a relationship in which both species benefit |
| commensalism | a relationship in which one species benefits and the other is neither helped or harmed |
| parasitism | a relationship in which one organism lives in or on the other, harming it |
| parasite | the organism that lives in or on another and benefits |
| host | the organism that is harmed by another that is living in or on it |
