Objectives:
1. Explain the difference between abiotic and
biotic factors.
2. Describe the levels of biological organization
3. Differentiate between an organisms habitat and
its niche.
Vocabulary
Ecology
Biosphere
Biotic factor
Abiotic factor
Population
Biological
Community
Ecosystem
Biome
Habitat
Niche
Predation
Symbiosis
Mutualism
Commensalism
Parasitism
Ecology
• Ecology: the study of relationships between
living organism, and their interaction with
their environments.
• Biosphere: The portion of the earth that
supports life.
Biotic and Abiotic Factors
• Biotic Factors: The living factors in an
organism’s environment.
• Abiotic Factors: The non-living factors in an
organism’s environment.
Levels of Organization in ecology
Organisms
Population
Biological community
Ec osystem
Biome
Bioshpere
organism
• The lowest level of ecological classification is
the single organism.
• (Example: one single fish)
Population
• A population is all the individuals of a single
species that share the same geographic
location at the same time.
• (example: a school of fish)
Biological Community
• Community: A group of interacting
populations that occupy the same geographic
area at the same time.
Ecosystem
• Ecosystem: includes a community and all the
abiotic factors that effect it.
Biome
• Biome: a large group of ecosystems that share
the same climate and have similar types of
communities.
• (Example: a marine biome)
Habitat and Niche
• Habitat: the area where an organism lives.
• Niche: the role or position that an organism
has in it’s environment. (it’s job).
Community Interactions
Community Interactions
• Competition: occurs when more than one
organism uses a resource at the same time.
• Competition for food, water, space, light, and
mates.
• Predation: The act of one organism
consuming another organism for food.
Community Relationships Continued
• Symbiotic relationship: A close relationship
that exists when two or more species live
together.
Three types of Symbiotic Relationships
• Mutualism: when the two or more organisms
both benefit from the relationship.
• Commensalism: a relationship when one
organism benefits and the other organisms is
neither helped nor harmed.
• Parasitism: a relationship when one organism
benefits at the expense of another organism.