Chapter 20-3 Vocabulary

Chapter 20 Section 3 Vocabulary

1. Adaptation   

     A behavior or physical characteristic that allows an organism to survive or reproduce in its environment.


2. Commensalism   

      A relationship between two species in which one species benefits and the other is neither helped nor harmed.


3. Competition   

     The struggle between organisms to survive as they attempt to use the same limited resource.


4. Host   

     The organism that a parasite or virus lives in or on.


5. Mutualism   

     A close relationship between organisms of two species in which both organisms benefit.


6. Natural Selection       

      A process by which individuals that are better adapted to their environment are more likely to survive and reproduce than others of the same species.


7. Niche   

     The role of an organism in its habitat, or how it makes its living.


8. Parasite   

     The organism that benefits by living on or in a host in a parasitism interaction.


9. Parasitism       

     A relationship in which one organism lives on or in a host and harms it.


10. Predation       

     An interaction in which one organism kills another for food.


11. Predator   

     The organism that does the killing in a predation interaction.


12. Prey   

     An organism that is killed and eaten by another organism


13. Symbiosis   

     A close relationship between two organisms of different species that benefits at least one of the organisms

Back to Unit 1