1. Unit 12 Vocabulary

2. 10% Rule
Only 10% of the energy present at one feeding is passed on to the next feeding level

3. Commensalism
A symbiotic relationship between species in which one species is helped and the other is unaffected

4. Energy Pyramid
Diagram that demonstrates the flow of energy through a food chain

5. Mutualism
A symbiotic relationship between two species in which both species benefit

6. Parasitism
A symbiotic relationship in which one organism (parasite) benefits and the other (the host) is generally harmed but not killed

7. Symbiosis
A close relationship between two species

8. Producer
An organism that can make it’s own energy through photosynthesis or chemosynthesis

9. Primary Consumer
In a food chain, organisms that eat producers

10. Secondary Consumer
In a food chain, an organism that feeds on producers (plant-eaters); also called a predator

11. Tertiary consumers
In an ecosystem, a predator that feeds on other predators

12. Decomposers
An organism that breaks down tissue and releases nutrients and carbon dioxide back into the ecosystem

13. Omnivore
an organism that eats both plants and animals.

14. An organism that feeds only on plants
Herbivore
An organism that feeds only on plants

15. Carbon Cycle
The continual transfer of carbon dioxide and oxygen between living things and the environment

16. Water Cycle
Cycle in which water moves through the environment, through the process of evaporation, condensation and precipitation

17. Nitrogen Cycle
In the environment, the movement of nitrogen between the living and non-living parts of an ecosystem

18. Natural Selection
Process by which organisms change over time as those with traits best suited to an environment pass their traits to the next generation.

19. Survival of The Fittest
A natural process resulting in the evolution of organisms best adapted to the environment

20. Food Chain
Series of stages that shows the transfer of energy from producers to consumers to decomposers

21. Food Web
In an ecosystem, arrangement of several overlapping food chains

22. Predator
Animal that kills and eats other animals

23. Host
Organism that supports a parasite

24. Parasite
Organism that feeds on cells, tissues or fluids of another living organism