Transcript Slide 1
NAME
ENERGY
SOURCE
EXAMPLE
Producer
Makes own food
Grass, Trees
Consumer
Eating Other
Organisms
Mice, Humans,
Starfish
Herbivore
Producers
Cows, Deer
Carnivore
Omnivore
Decomposer
Other
Lions, Hawks
Consumers
Producers and
Bears, Pigs,
Humans
Consumers
Dead Organisms Fungi, Bacteria
Primary Energy Source
The rate at which organic
material is produced by
photosynthetic organisms in an
Organisms
first primary
capture
ecosystemthat
is called
solar energy,
the producers,
productivity
include plants, some kinds of
Consumers
are those
organisms
bacteria,
and algae.
that consume plants or other
organisms to obtain the energy
necessary to build their
molecules
Autotrophs are organisms
that use
Energy from sunlight or
Inorganic substances to make
Organic compounds.
Like plants use
sunlight to
Make glucose.
Heterotrophs are organisms that
Must get energy from food instead
Of directly from sunlight.
We are heterotrophs because
We can’t make our own food
In our cells.
Instead we use cellular
respiration
To “burn” fuel in our bodies.
Directly or indirectly, almost all
of the
Energy in living systems needed
for
Metabolism comes from the sun.
Cellular respiration is the
Process of breaking down food
To yield energy.
This is essentially photosynthesis
In reverse.
6CO2 + 6H2O + Light
C6H12O6 + 6O2
Trophic Levels
Ecologists study how energy
moves through an ecosystem by
assigning organisms in that
ecosystem to a specific level,
called a trophic level, in a
graphic organizer based on the
organism’s source of energy.
Energy moves from one trophic
level to another
Trophic Levels
Trophic Levels: First Level
The lowest trophic level of any
ecosystem is occupied by the
producers, such as plants, algae,
and bacteria
Producers use the energy of the
sun to build energy-rich
carbohydrates
Trophic Levels: Second Level
At the second trophic level are
herbivores, animals that eat
plants or other primary
producers. They are the primary
Most herbivores
consumersrely on
microorganisms,
such
as
bacteria
A herbivore must be able to break
and
protists,
in
their
gut
to
help
down a plant’s molecules into
digest
cellulose
usable compounds
Trophic Levels: Third Level
At the third trophic level are
secondary consumers, animals
that eat herbivores. These
Dentrivores
organisms
that
animals are are
called
carnivores
obtain their energy from the
organic
wastes
andas
dead
bodies
Some
animals,
such
bears,
are
that
produced
atcarnivores;
all trophic
both are
herbivores
and
levelsomnivores
they are called
Bacteria and fungi are known as
decomposers because they cause
decay
Decomposition of bodies and
wastes releases nutrients back
into the environment to be
recycled by other organisms
A food chain is
a sequence in
Which energy is
transferred
From one
organism to the
Next as each
organism
Eats another.
A food web shows many of the
Feeding relationships in
An ecosystem.
In most ecosystems, energy does not
follow simple straight paths because
animals often feed at several trophic
levels. This creates an interconnected
group of food chains called a food web
Energy Transfer
During every transfer of energy
within an ecosystem, energy is
lost as heat.
Thus, the amount of useful
energy available to do work
decreases as energy passes
through an ecosystem
The loss of useful energy limits
the number of trophic levels an
ecosystem can support
To better determine the amount
of energy present in trophic
levels, ecologists measure
biomass
Biomass is the dry weight of tissue
and other organic matter found
in a specific ecosystem
Each higher level on the pyramid
contains only 10% of the biomass
found in the trophic level below
it
The Pyramid of Energy
An energy pyramid is a diagram in
which each trophic level is
represented by a block, and the
blocks are stacked on top of one
another, with the lowest trophic
level on the bottom
Energy Transfer Through
Trophic Levels
Water moves between the
Earth’s surface and
The Atmosphere is a process
Called the Water Cycle.
Carbon flows through
Ecosystems when plants make
Food and consumers eat produces
And then decomposers start the
Process over again.
But humans have a huge impact
The this due to our burning
Of fossil fuels.
The Carbon Cycle
All organisms need Nitrogen.
The good news is that it is
All around us in huge quantities.
The bad news is that almost all
Organisms can’t use it from the
Air.
So we get it from nitrogenFixing bacteria that allows it
To be used by plants.
Succession is a regular
Pattern of changes over
Time in the types of species
In a community.
The community that eventually
Forms if the land is left
Undisturbed is called
Climax community.
Succession that occurs on a
Surface where an ecosystem
Has previously existed is called
Secondary Succession.
Pioneers are the first organisms
To colonize any newly available
Area and start the process
Of succession.
Natural fires caused by
Lightning are a necessary part
Of secondary succession in
Some communities.
National forest rangers
Sometimes allow natural fires
To burn unless they threaten
Human life or property.
Succession that occurs on
Surfaces where no
Ecosystem existed before is
Called Primary Succession.
Primary succession is much
Slower than secondary
Succession because it begins
Where there is no soil.