1. Organisms and Their Relationships
Chapter 2
Section 1

2. Learning Targets
I can define and give examples of each level of ecological organization
I can contrast biotic and abiotic factors
I can explain the types of symbiosis
I can describe the effects of competition and predation

3. Ecology
Scientists can gain valuable insight about the interactions between organisms and their environment.
Each organism, regardless of where it lives, depends on nonliving factors found in its environment and on other organisms living in the same environment, for survival

4. Ecology
Ecology – the scientific discipline in which the relationships among living organisms as well as the interactions the organisms have with their environment are studied
Individuals who study ecology are known as Ecologists

5. The Biosphere
Because ecologists study organisms and their environments, their studies take place in the biosphere
Biosphere: the portion of Earth that supports life
Bio means “life” and sphere means “ball”

6. The Biosphere
Biotic Factors – living factors in an organism’s environment
Interactions of organisms are important for the health of all species in the same geographic location.

7. The Biosphere
Abiotic Factors – nonliving factors in an organism's environment
Factors might include: temperature, air or water currents, sunlight, soil type, rainfall, or available nutrients
Organisms are adapted to surviving in the abiotic factors that are present in their natural environment.
If placed in a different environment, they might die if they cannot adjust quickly

8. Levels of Organization
The biosphere is too large and complex for most ecological studies. So, scientists have broken down the biosphere to make it easier to study.
Levels of Organization:
Organism
Population
Biological Community
Ecosystem
Biome
Biosphere

9. Levels of Organization
Organism: individual organisms themselves
Population: individual organism of a single species that share the same geographic location at the same time
Biological Community: a group of interacting populations that occupy the same geographic area at the same time

10. Levels of Organization
Ecosystem: a biological community and all of the abiotic factors that affect it
Biome: a large group of ecosystems that share the same climate and have similar types of communities
Biosphere: all of the biomes on earth combined

11. Ecosystem Interactions
Interactions between organisms are important in an ecosystem.
Chances for survival of any one species increases by using available resources in different ways
Habitat – an area where an organism lives
Might be a single tree or a whole forest
Niche – the role or position that an organism has in its environment

12. Community Interactions
Organisms that live together in a biological community constantly interact.
These interactions shape an ecosystem
Competition: occurs when more than one organism uses a resource at the same time
Ex: during a drought, water is scarce and the strong organisms will compete with the weak organisms for water

13. Predation Some species get their food by eating other organisms
Predation: the act of one organism consuming another organism for food
Ex: Lion (predator) stalks Zebra (prey)
Not all predators are animals Ex: Venus Fly Trap

14. Symbiotic Relationships
Some species survive because of the relationships they have developed with other species.
Symbiosis: The close relationship that exists when two or more species live together
There are 3 types: mutualism, commensalism, and parasitism

15. Symbiotic Relationships
Mutualism: relationship between two or more organisms that live closely together and benefit from each other
Ex: Lichen
Commensalism: a relationship in which one organism benefits and the other organism is neither helped nor harmed
Parasitism: one organism benefits at the expense of another organism

16. Symbiotic Relationships