1. Two or more organisms living together in a close association
Symbiosis
Two or more organisms living together in a close association

2. Three kinds of symbiosis
Mutualism Commensalism Parasitism

3. Mutualism A symbiotic relationship in which both species benefit
Ex. The bee benefits by obtaining food (nectar) and
the plant benefits when the flowers are pollinated

4. Mutualism
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Both organisms benefit

5. Commensalism
A symbiotic relationship in which one species benefits and the other species is not harmed or benefited. Ex. Barnacles on this Gray Whale are benefited but the whale is not harmed or benefited.
Talk to the students about how Barnacles benefit from being attached to the whale. The use them for motility and for easy access to food.

6. One benefits and the other is neither benefited nor harmed
Commensalism
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Students must complete this circle map on their own. Add examples that represent commensalistic relationships.
One benefits and the other is neither benefited nor harmed

7. Parasitism One member benefits and the other member is harmed
The organism that benefits is called the parasite
The organism that is harmed is called the host

8. One is benefited and the other is harmed
Parasitism
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One is benefited and the other is harmed

9. Predation
The act of killing one
organism for food.

10. One organism benefits and the other is harmed
Predation
One organism benefits and the other is harmed

11. Two species using the same resources for survival
Competition
Two species using the same resources for survival
Food
Shelter
living space
light
mineral nutrients
water
Usually occurs when there is a limit or shortage of the above supplies in the ecosystem.

12. The wolves and the moose compete for survival
Notice how as one population of organisms increases the other population of organisms decreases
This is due to the fact that there are only a limited supply of resources in the area to support the population size of both organisms