ecosystem - Mrs. V. Murphy`s Science Class
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Transcript ecosystem - Mrs. V. Murphy`s Science Class
Energy Flow Through an
Ecosystem
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Nearly all of Earth’s energy begins with
the sun!
• Sunlight is necessary for organisms to produce
their own energy.
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Organisms that make their own
energy (glucose) during
photosynthesis are called
PRODUCERS. Plants are producers
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Photosynthesis
• The process by which plants (producers)
make food is called "photosynthesis".
• "photo" = light
"synthesis" = putting together
• This happens to EVERY plant, and to some
bacteria and algae, too. Without
photosynthesis, plants wouldn't exist
Cellular Respiration
• A process in which plants, animals, and
humans take in oxygen and release carbon
dioxide.
• Plants- Take in oxygen through the stoma and
use it to get the energy they need to burn
food.
• Humans and animals- Take in oxygen to help
them burn digested food and get energy.
http://www.neok12.com/php/watch.php?v=zX787d5
85f475a015b5c7c06&t=Photosynthesis
CELLULAR RESPIRATION
Chemical reaction that converts glucose and
oxygen into usable energy that allows organisms
to perform the necessary life processes.
6O2 + C6H12O6 6H2O + 6CO2 + energy
It’s a cycle! The O2—
CO2 cycle or
photosynthesis/
respiration cycle.
Video
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Interactions Within Ecosystems
Ecology—the scientific study of interactions
between different organisms their
environment
An ecologist would study organisms that live in an
ecosystem. Ecosystems are a network of living and
non-living things that interact. The size of the
ecosystem depends on the shared similarities
between living and non-living things—can be small
or very large.
Biotic—living factors that influence an ecosystem
Abiotic—non-living factors that influence an
ecosystem
Who makes up an ecosystem?
• Organisms within an ecosystem are
classified into:
–Individuals—singular organisms
–Populations—all the individuals that belong
to one species in a habitat
–Communities—all the combined
populations in a habitat
• Ecological Niche – an organism’s role in
an ecosystem. This includes its: place in
the food web, habitat (home), breeding
area, etc.
• Within ecosystems, each organism has its
own specific niche. No two species fulfill
exactly the same role.
Example: The ecological niche of a sunflower
growing in a backyard includes: absorbing
light, water and nutrients (for
photosynthesis), providing shelter and
food for other organisms (e.g. bees, ants,
etc.), and giving off oxygen into the
atmosphere.
• If a new, exotic species is introduced into an ecosystem, it
will have to compete with any species that is already
fulfilling the same niche the new species would. Eventually,
one of the two species will be out-competed and cannot
survive in the ecosystem. During this process, the entire
ecosystem will be disrupted.
Limiting Factors are…
• Environmental conditions that may prevent
populations from reaching their biotic
potential. This means that the ecosystem
could sustain more members if the limiting
factor was not there.
• Limiting factors may be biotic or abiotic
Limiting Factors cont…
ABIOTIC FACTORS
• too much or too little light
• temperature too cold or too
warm
• harmful chemicals in the
environment
BIOTIC FACTORS
•
•
•
•
insufficient food
excessive predators
diseases or parasites
diminished ability to
compete with other
species
Terrestrial Ecosystems
• Terrestrial ecosystems are limited by four major abiotic
factors:
1. Soil
2. Available Water
3. Temperature
4. Sunlight
Carrying Capacity
• Is the maximum number of individuals of a
single species that can be supported in an
ecosystem at a particular time. This is
determined by the availability of food,
presence of predators, disease and other
resources. If a population exceeds the
carrying capacity, there will be a decline in
number until the population re-stabilizes.
Aquatic Ecosystems
• These ecosystems are affected by three major
abiotic factors:
– chemical environment (level of dissolved
oxygen)
– light levels (this is the most important
abiotic factor)
– Water temperature
Relationships within
an Ecosystem
Organisms that cannot make their
own energy are called CONSUMERS.
Consumers eat producers to get energy…
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Consumers that eat producers to get
energy:
• Are first order or
primary consumers
• Are herbivores
(plant-eaters)
Most of the energy the primary
consumer gets from the producer is
used by the consumer.
Some of the energy moves into
the atmosphere as heat.
A consumer that eats another
consumer for energy:
• Is called a secondary or
second order consumer
• May be a carnivore
• May be a predator
• May be a scavenger
A consumer that eats a consumer that
already ate a consumer:
• Is called a third order or
tertiary consumer
• May be a carnivore
• May be a predator
• May be a scavenger
Consumers that eat producers & other
consumers
• Are called omnivores
• Omnivores eat plants
and animals
Consumers that eat other dead
consumers are called
scavengers
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All dead and decaying matter at each
level is broken down by decomposers
such as bacteria and fungi. The recycling
of raw materials and nutrients back into
the soil after decomposition—a process
call biodegradation, is vital to all
ecosystems.
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The transfer of energy from the sun
to producer to primary consumer
then to higher order consumers can
be shown in a FOOD CHAIN.
Brainpop Food Chains
Another way of showing the transfer
of energy in an ecosystem is the
ENERGY PYRAMID.
Energy pyramids show
• That the amount of available
energy decreases down the
food chain
• It takes a large number of
producers to support a small
number of primary
consumers
• It takes a large number of
primary consumers to
support a small number of
secondary consumers
Food Webs:
•Are
interconnected
food chains
•They show the
feeding
relationships in an
ecosystem
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Identify the Producers, Consumers, & Decomposers:
Count the
Food
Chains!
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