The Biosphere and Levels of Organization
The Biosphere and Levels of Organization
The Biosphere and Levels of Organization
What is ecology?
Describe how an ecosystem is divided into
different levels of organization.
OBJECTIVE
Ecology
• Ecology – the study of interactions among
organisms and between organisms and their
environment
• Interdependence – dependence of every
form of life on other living things and
natural resources (air, water, land) in its
environment
Levels of Organization
• Biosphere – largest, portions of planet
where life exists (land, H2O, air)
– 8 km above to 11 km below
• Biome – group of ecosystems with same
climate (temp. and rainfall)
• Ecosystem – collection of all organisms in
a particular place together with the abiotic
(physical) environment.
Levels of Organization
• Community – groups of different
populations that live together in a defined
area.
• Population – groups of individuals of same
species in same area.
• Species – group of organisms so similar
that they can mate and produce fertile
offspring.
Levels of Organization
September 9, 2022
Decomposing Fox
Water Cycle
Water Cycle
1. Water enters the atmosphere by:
• Evaporation – water changes from a liquid to a
gas
• Transpiration – Evaporation through leaves
2. As water rises it cools condenses into tiny
droplets that form clouds.
3. Droplets return to Earth as precipitation.
4. Water enters the rivers, ground water, ocean
or plant roots to restart cycle.
Making Clouds
Nitrogen Cycle
Nitrogen Cycle
1. Nitrogen gas makes up 78% of atmosphere
2. Nitrogen Fixation: bacteria take nitrogen
gases and turn it into ammonia, nitrite, and
nitrate.
3. Plants and animals use nitrate to make amino
acids.
4. Animal dies and decomposes returning nitrates
to the soil.
5. Denitrification: other bacteria convert nitrates
into nitrogen gas.
Nutrient Limitation
• Primary Productivity – the rate at which
organic molecules are created by producers
2. Predation
• One organism (predator)
captures and feeds on another
(prey).
Battle at Kruger Lake
4.2 Community Interactions
3. Symbiosis
• Mutualism – both benefit
Ex: Flowers & insects
Egrets & Alligators
Clown Fish & Sea Anemone
• Commensalism – one
benefits, the other is not
helped nor harmed
Ex: Barnacle & Whale