Download Ecology

Ecology
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Ecology is the scientific study of the
interaction between organisms and
between organisms and their
environment.
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Levels of Organization
1.
2.
3.
4.
5.
Biosphere
Ecosystem
Community
Population
Organism
Ecological Methods
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Scientists conduct research using 3 basic
approaches.
1. Observing – could be behavior
observations about an animal.
2. Experimenting – test a hypothesis
3. Modeling – gain insight into complex
phenomena like global warming.
Notes: 3-2 Energy Flow
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Sunlight is the
main energy
source for life on
Earth.
Autotrophs –
capture energy
from sunlight and
use that energy to
produce food. Also
called producers.
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Heterotrophs – rely on other organisms for
their energy and food supply. Also called
consumers.
Herbivores – eat plants
Carnivores – eat animals
Omnivores – eat both
Detritivores – eat dead matter
Food Chains
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Food Chains – a series of steps in which
organisms transfer energy by eating and
being eaten.
Example: plankton –dragonfly-salamandersnake
Food Web
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Food Web – links all the food chains in
an ecosystem together.
Trophic Level
Each step in a food chain/web is called
a trophic level.
(herbivore)
Pyramids – 3 types
1. Energy Pyramid – transfer of energy from one
trophic level to the next. Measured in kcals.
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**10% rule** - only 10% of the energy is
transferred from one trophic level to the next.
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Why?
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It is lost in respiration, movement and
reproduction.
Energy Pyramids Cont’d
100 K/cals
1,000 K/cals
10,000 K/cals
Types of Pyramids
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2. Biomass Pyramid – transfer of biomass
from one trophic level to the next.
Types of Pyramids
3. Pyramid of Numbers – the total
number of individuals at each trophic
level. (may not look like a pyramid)