Ecology Part 2 Notes Guide
KEY CONCEPT
Food chains and food webs model the flow of energy in an ecosystem.
A food chain is a model that shows a sequence of feeding relationships.
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A food chain links species by
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A food
Consumers are not all alike.
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Herbivores eat
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Carnivores eat
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Omnivores eat
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Detritivores eat
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Decomposers are
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Specialists
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Generalists are
Trophic levels are the nourishment levels in a food chain.

Primary consumers

Secondary consumers

Tertiary consumers are

Omnivores
A food web shows all the interconnected feeding relationships in an ecosystem.
• An organism may have
• A food web
Water cycles through the environment.


Organisms all have bodies made
Elements essential for life also cycle through ecosystems.

A biogeochemical cycle

The main processes involved in the oxygen cycle are
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Oxygen cycles
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Carbon is the building block of life.
•
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The carbon cycle moves
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Carbon is emitted by the
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Some carbon is stored for long periods of
time in areas called
The nitrogen cycle mostly takes place underground.
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Some bacteria convert
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Some nitrogen-fixing bacteria live in
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Ammonia released into the
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Nitrifying bacteria change the.
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Nitrogen moves through the food
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The phosphorus cycle takes place at and below ground
level.
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Phosphate is released by the
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Phosphorus moves through
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Phosphorus leaches into groundwater
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Both mining and agriculture
Pyramids model the distribution of energy and matter in an ecosystem.
An energy pyramid shows the distribution of energy among trophic levels.
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Energy pyramids compare
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Between each tier of an energy pyramid,
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Only
Other pyramid models illustrate an ecosystem’s biomass and distribution of organisms.
• Biomass is a measure of
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A pyramid of numbers
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A vast number of producers
ene
rgy
energy