Download Ecology `15 Notes

Name _________________________________________________________________
Period ________
Notes: Food Chains and Levels of Organization in Ecology
_____________ factors- all living organisms inhabiting the Earth
_____________ factors- nonliving parts of the environment (i.e. temperature, soil, light, moisture, rocks)
Levels of Organization in Ecology
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Organism → ______________________ → Population → Community → Ecosystem → ___________________ →
Biosphere
Species - Group of organisms so similar to one another that they can ________________ and produce
______________________ offspring.
Population - Groups of individuals that belong to the same ____________________ and live in the same
____________________.
Communities - Assemblages of different _____________________ that live together in a defined area.
Ecosystem - Collection of all _____________ and nonliving things in a determined place.
Biome - Group of ecosystems that have the same ____________________ and similar dominant
________________________________.
Biosphere – Part of the planet in which
all life exists, including land, water, and air (All _______________ combined).
– It extends from about 8
kilometers above Earth's
surface to as far as 11
kilometers below the
surface of the ocean.
Niche
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Niche – An organism’s niche describes its role or _________________ in the ecosystem
The niche describes the _____________________ of the organism in the food chain
Can be compared to a person’s _____________________________
Eat and Be Eaten
1. Herbivores - _____________________________
2. Carnivores – _______________________________
3. Omnivores – eat both plants and animals
4. Decomposer – ____________________ dead organic matter chemically (bacteria)
5 Detritivores – ________________on plant and animal remains (crab, earthworm)
1. Decomposer– break down dead organic matter __________________________
• Includes:
&
2. Detritivore - _____________ on plant and animal remains
• Includes:
1. maggots
2. dung beetles
3. ________________________________
4. sow bugs (rolly polly)
Food Chain vs. Food Web
1. Food Chains follow just ____________ path as animals find food.
2. Food Webs follows _______ possible energy paths
***Both food chains and food webs show the ______________of energy in an ecosystem.
Trophic Levels
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Trophic Levels - corresponds to the different ________________ or ________________ in the food chain.
– Represents the feeding ________________________ in a food chain such as primary producers,
herbivore, primary carnivore, etc.
Food Chains Always Begin With _________________________ And End With ____________________.
Matter vs. Energy
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Matter – Has _____________, takes up __________________,
is usually a “thing”
Energy – Not like matter, does ___________ have mass,
_______________________take up space, energy moves matter
– Forms of energy: light, heat, sound, motion,
and ___________________________
How Much Energy is Passed On?
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Only 10% is passed on to the next trophic ____________________
The other 90% is lost/given off as ________________
Food Chains: Matter and Energy
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As you go along a food chain, the matter and energy ________________________.
This can be represented in a ________________________.
Pyramids
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Pyramids are ___________________ at the bottom…more matter and energy are at the bottom of the
pyramid!
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Ecological Pyramid - Diagram that shows the ____________________ amounts of energy or matter
contained within each trophic level in a food chain or food web.
Two Types of Ecological Pyramids
1. Pyramid of Biomass – Represents the biomass
at each ____________________ level
 Biomass – Total amount of living
________________ within a trophic level
 Usually expressed in grams
per unit area.
 As you go along a food chain, the
amount of ___________________ decreases!
2. Pyramid of Numbers – Represents the
_______________________ of organisms at each
trophic level
 As you go further down a food chain, the
numbers of organisms ____________________
because there is less energy available!
 Exception - If you have a large producer
such as a tree), the pyramid of numbers
may look _____________________ in shape.
Name ___________________________________________________________________
Period ________
Notes: Interactions
Symbiotic Relationships
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Symbiotic Relationships – Interactions between two or more organisms; Two different species
__________________ a relationship (interact) in order to ensure ___________________________
Predation
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The capturing of _____________ as a means of maintaining life
– One organism benefits; One organism is _____________________
Parasitism
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One organism (the parasite) benefits and the other (the host) is _____________________,
but is still _________________.
– Examples – ________________ and a dog, mosquitos and
humans, __________________________ infections such as a
sore throat
• Because the parasite needs the _______________ to remain alive, it is typically
advantageous for the parasite NOT to ____________ its host
Mutualism
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Relationship that benefits ________________ species.
– Examples of Mutualism
1. _____________________
2. Seed Dispersal
3. _____________________
Commensalism
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When one species benefits from the relationship and the second species is ______________________.
• Examples -Barnicles and ________________________
Carrying Capacity and Predators
Carrying Capacity
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_____________________ of species that can be _______________________________ by an ecosystem.
Population Growth is Represented by one of two graphs:
– Exponential - individuals in a population reproduce at a constant rate (Ideally happens IF
there are unlimited resources) = (J-curve)
– Logistic – The growth of a population slows or stops as resources become less available (Scurve) ***This is what our Population is represented with***
Factors that Affect Population Size
1. Number of _______________
2. Number of _______________
3. Number of individuals that enter or leave a population
– __________________ = movement of individuals INTO an area (growth)
– __________________ = movement of individuals OUT of an area (shrink)
Limiting factor - any biotic or abiotic factor that restricts the existence of organisms in a specific
environment.
Limiting factors:
a. Density independent: factors that affect all members of the population ___________ if population
is dense or not.
 Natural disasters: floods, earthquakes, wildfires, tornadoes, mudslides,
pollution, habitat destruction
b. Density dependent: factors that affect ________________ populations
 EX: competition, predation, crowding and stress, parasitism, and disease
Competition
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Competition – A ____________________ between organisms for the same ________________________; The
fitness of one of the organisms is __________________________ by the presence of another.
– Limited supply of at least one ________________________ used by both organisms is required
• Example: Animals compete for food, mating, or ______________________ and plants can
compete for water, food, minerals, ___________________________.
Predators
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Organism that ___________________ and _______________ other organisms.
– Can be _________________________ or omnivores
The Importance of Predators
– We need them to control the ______________________________
– They also get rid of weak, crippled, stupid, stunted, and diseased organisms (survival of the
fittest)
Ecological Succession
Ecosystems are constantly changing in response to natural and human disturbances. Succession is a
series of predictable ______________ that occurs in a community over ____________.
Causes:
1. _________________________________________ land
2. Climate ___________________________________
3. Introduce nonnative species
4. ______________________________________________________________
 Natural, gradual changes in the types of species that live in an area; can be primary or secondary
1. Primary succession
a. Begins in a place ___________________________________________(Ie.
)
Called Pioneer species
b. Starts with the arrival of living things such as ______________ that don’t need soil to survive
c. Lichens add organic matter and break down rock into soil
d. Then simple plants like ________________ & ___________________ start to grow in new soil
e. Simple plants start to die, soil thickens allowing flowering plants to begin to grow then
small shrubs and trees, then ______________ and small animals can survive.
2. Secondary Succession
a. Begins in a place ____________________________________ and once was home of living
organisms
b. Occurs faster and has different pioneer species than primary succession. (ie.
)
Climax Community
A ______________ group of plants and animals that are the end result of succession.
_ Grasses in ____________________ or ___________________in deserts.
Name _________________________________________________________________ Date_______________________ Period _________
The Carbon Cycle
Why is Carbon important?
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All _________________ things are made of carbon!!!
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Carbon Does Not Stay Still – It Is On the Move!
1. In the atmosphere, carbon is attached
to some oxygen in a gas called ______________
______________________.
2. Plants use carbon dioxide and sunlight
to make their own food and grow. The
carbon becomes part of the plant.
3. Animals consume plants. The carbon
becomes part of the ______________________.
4. Plants that die and are buried may turn
into fossil fuels made of carbon like _______________ and oil over millions of years.
5. When humans _______________ fossil fuels, most of the carbon quickly enters the atmosphere as
________________________________.
Photosynthesis
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Using light energy, plants combine carbon dioxide (CO2) from the atmosphere and water (H20) to
form ____________________ and ________________________ in the process of photosynthesis.
sunlight
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Carbon Dioxide + Water → Sugar
What is Sugar (Glucose) Used For?
1. Source of _________________________
2. Building _______________________ for other compounds
such as proteins,
oils, and starches.
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Oxygen
Respiration
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In respiration, the compounds containing carbon are ________________________________, and carbon
dioxide is ______________________________.
Plants, _________________________, and microorganisms all carry out respiration!
Is the Carbon Cycle Balanced?
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The Carbon-Oxygen cycle is _____________ of balance.
There is more carbon dioxide being _________________________ into the atmosphere than is being
_________________________.
Combustion
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Most of the carbon dioxide is produced during the process of ________________________ called
combustion.
When compounds containing carbon (wood, coal, or oil) are burned, the carbon is chemically
combined with oxygen, and _________________________________is released.
The use of carbon dioxide by plants during photosynthesis is a much ____________________ process.
As a result of the imbalance between these two processes, the level of carbon dioxide in the
atmosphere is ______________________.
Decomposers
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When organisms die, decomposers break down the _____________________ compounds in
their bodies, and carbon dioxide is _______________________ to the atmosphere.
During decomposition (decay), other chemicals are also ____________________ to the soil or released
into the air. One of these chemicals is ____________________.
The Nitrogen Cycle
Nitrogen
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Plants and animals need nitrogen to make ______________________.
How Do PLANTS Get Nitrogen?
– Special _________________________, in the soil and water, must change or “fix” nitrogen gas (N2)
into nitrogen ________________________ (NO3-) or ammonium ions (NH4+) that plants can
_________________.
– These bacteria are called nitrogen-fixers.
• Most nitrogen-fixing bacteria live in little houses, or _________________, on the
__________________ of plants called legumes.
• Legumes - Members of a large family of plants that include _______________,
beans, alfafa, and ___________________.
• Nitrogen Fixers have a ____________________________ relationship with the plants
• The plants provide food and cover for the bacteria, and the bacteria convert
nitrogen gas into ______________________ for the plant.
How Do ANIMALS Get Nitrogen?
– Animals get nitrogen from plants or from other plant-eating animals, in the _________________
of protein.
– Animals must ____________ protein to get nitrogen! We can’t _____________________ in nitrogen!
How is Nitrogen Recycled?
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Nitrogen is recycled by special ______________________ that break down the nitrogen compounds
(proteins) in _________________ plants and animals, and in animal wastes.
If plants do ________ use the nitrogen compounds as fertilizer, special forms of bacteria may
____________________ it. These bacteria convert the unused fertilizer into nitrogen ___________ and
release it into the atmosphere.
Lightning and the Nitrogen Cycle
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Lightning plays a __________________ role in the nitrogen cycle.
Lightning _________________________ nitrogen and oxygen in the atmosphere.
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– The “fixed” nitrogen, (which is dissolved in the _______________) enters the _________________.
The burning of ___________________________________ is another source of nitrogen.
– Combustion causes nitrogen and oxygen to _________________________ creating nitrogen oxides
(NOx).