1. Lessons 2 & 3 Interactions of Organisms and Populations
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2. How are living things organized?
Organisms
Populations
Communities
Ecosystems
Biomes

3. A living thing is called an organism.
Example: a deer

4. All of the organisms of the same species that live in an area at the same time is called a population.
Example: a herd of deer

5. All the populations of all species that live in an area is called a community.
Example: deer + rabbits + bears

6. All the organisms living in an area, as well as the non-living parts of their environment, is called an ecosystem.
Example: deer + rabbits + bears + water + temperature + sunlight + soil + air

7. Large geographic areas that have similar climates and ecosystems are called biomes.
Example: tundra, taiga, desert, etc.

8. There are different kinds of relationships between the organisms in an ecosystem.

9. Predator/Prey
An organism that hunts and eats another organism is called a predator.
The organism that the predator hunts and eats is called prey.

10. Which one is the predator and which one is the prey?
zebra
lioness

11. Which one is the predator and which one is the prey?
snake
roadrunner

12. Which one is the predator and which one is the prey?
fish
osprey

13. Which one is the predator and which one is the prey?
fox
hare

14. Symbiosis
Symbiosis is when two organisms live together, temporarily or for a longer time, and at least one of the organisms benefits from the relationship.

15. Different kinds of symbiosis
Mutualism
Commensalism
Parasitism
one organism benefits
one organism is unaffected
+ 0
one organism benefits
one organism is harmed
+ -
both organisms benefit
+ +

16. More about Parasitism
The organism that benefits in a parasitic relationship is called the parasite.
The organism that is harmed in a parasitic relationship is called the host.

17. Identify the type of relationships in the following examples:

18. Moray Eel with Cleaner Fish
Moray Eel gets a clean mouth. Cleaner Fish gets a meal.
Mutualism

19. Cattle with cattle egrets
Cattle stir up insects as they eat grass. Egrets hang around and eat insects.
Commensalism

20. Acacia plant with ant galls
Bull horn acacia trees provide nutrients and housing for
acacia ants. Acacia ants attack herbivores that try to eat the leaves.
Mutualism

21. Protection. Anemone is unaffected.
Clown fish with anemone
Clown fish
gets
Protection. Anemone is unaffected.
Commensalism

22. Antelope with oxbird
Antelope gets rid of parasites. Oxbird gets a meal.
YouTube - JumpStart Symbiotic Harmony Song
Mutualism

23. Taenia worm in human eye
infects human blood stream. Human may go blind.
Parasitism

24. Mr. Lee “Symbiosis”
YouTube - Mr. Lee - Symbiosis rap