3. Ecology- the scientific study of
interactions between organisms
and their environments,
focusing on energy transfer
 It is a science of
relationships.

4.  Definition:
 All external conditions and factors (living and
nonliving) that affect an organism or other specified
system during its lifetime

5. The environment is made up of two factors:
Biotic factors- all living organisms inhabiting the Earth
ex. How organisms interact/effect each other
Abiotic factors- nonliving parts of the environment
 temperature
 Soil
 Sunlight
 water/moisture
 air currents/wind
 Severe disturbances

6.  Temperature 0-50oC is the narrow range of temperatures
that can support life
 Too hot: above 50…important enzymes DENATURE
 Too cold: metabolism slows down…what is metabolism? (review notes from
beginning of year!)
 Set of chemical reactions that help break down and build up molecules to
get energy for life
 Organisms have made adaptations to extreme environments
 Prokaryotes in deep sea vents (extreme heat)
 Prokaryotes in frigid arctic waters (extreme cold)

7.  Product of abiotic forces (ice, rain, and wind) and
biotic forces (microorganisms, plants, and
earthworms) on rocks and minerals of Earth‟s crust
 Effects plants that grow in areas
 Dry, nutrient poor soil dominated by blue stem
grasses with long roots to obtain scarce moisture in
soil and narrow leaves that prevent excessive water
loss
 Soil/sand in aquatic environments also impacts
ecosystem
 Soil can be acidic or basic, nutrient rich or nutrient
poor
 This influences plants that grow in area, which
influence organisms that live there

8.  Energy source for ALL
organisms (except
chemosynthetic organisms)
 Terrestrial and aquatic
 Penetrates top 200 m of
the surface…affects algae
 Forests
 trees prevent sunlight from
reaching the
bottom…varying amounts of
sunlight creates
microhabitats…what does
that mean?
Habitat with conditions
different from the larger
surrounding environment
 PHOTOSYNTHESIS

9.  Dissolves gasses
 Universal solvent
 Organisms make adaptations to prevent water
loss (needles instead of leaves on trees and a
waxy cuticle)

10.  Affects distribution
 Moves clouds which carry precipitation
 Stirs up water which mixes up the nutrients in
lakes and streams
 Spreads pollen and seeds of plants

11.  Fires, hurricanes, droughts.
Floods and volcanic eruptions
 Some occur frequently and
organisms have made evolutionary
adaptations (prairie grasses)
 Some are infrequent (volcanic
eruptions) and organisms have no
voluntary adaptations

12. Biosphere
Ecosystem
Community
Population
Organism

13. Organism- any unicellular or
multicellular form exhibiting all of the
characteristics of life, an individual.
•The lowest level of organization

14. Population-a group of organisms of
one species living in the same place
at the same time that interbreed
and compete with each other for
resources (ex. food, mates, shelter)

15. Community- several interacting
populations that inhabit a common
environment and are interdependent.

16. Ecosystem- populations in a
community and the abiotic factors
with which they interact (ex.
marine, terrestrial)

17. Biosphere- life supporting portions
of Earth composed of air, land,
fresh water, and salt water.
•The highest level of organization

18. “The ecological niche of an
organism depends not only on
where it lives but also on what
it does. By analogy, it may be
said that the habitat is the
organism's „address‟, and the
niche is its „profession‟,
biologically speaking.”
Odum - Fundamentals of Ecology

19. Habitat vs. Niche
Niche - the role a species plays in
a community (job)
Habitat- the place in which an
organism lives out its life
(address)

20. Habitat vs. Niche
A niche is determined by the
tolerance limitations of an
organism, or a limiting factor.
Limiting factor- any biotic or
abiotic factor that restricts the
existence of organisms in a
specific environment.

21. Habitat vs. Niche
Examples of limiting factors-
•Amount of water
•Amount of food
•Temperature

22.  Earth rotates on an axis (23.5’)
 So sunlight hits Earth at different angles
 Creates Climate Zones
 Tropics
 Region between Tropic of Cancer (23.5’N) and
Tropic of Capricorn (23.5’S)
 Most direct sunlight
 Temperate Zones
 Latitudes between the Tropics and the Polar Zones
 Seasonal changes; no extreme heat or cold
 Polar Zones
 Region north of the Arctic Circle (66.5’N) and South
of the Antarctic Circle (66.5’S)
 Least amount of direct sunlight
 These climate zones are important and create BIOMES

25.  Our planet's rotation produces a force on all bodies
moving relative to the Earth
 Due to Earth's approximately spherical shape, this
force is greatest at the poles and least at the
Equator.
 "Coriolis effect” the force that causes the direction
of winds and ocean currents to be deflected
 Northern Hemisphere wind and currents deflected
toward the right
 Southern Hemisphere  wind and currents
deflected to the left.

26.  Weather
 Day-to-day conditions of Earth's atmosphere
 precipitation, humidity, temperature, etc.
 Changes every day
 Climate
 The average, year-after-year, conditions (temperature and precipitation) that prevail in a specific
region
 Microclimate
 Climate in a specific area that varies from the surrounding climate region
 Ex. The burrow of a Kangaroo rat in the New Mexico desert (dark and cool)