Transcript Cycles in Nature - Doral Academy High School

Water Cycle
The water cycle involves the processes of
evaporation, condensation, precipitation,
transpiration, percolation and runoff.
BrainPOP: Water Cycle
Percolation
Carbon Cycle
The process by which carbon moves
between organisms and their physical
environment.
BrainPOP: Carbon Cycle
CO2
Producers take in
CO2 during
photosynthesis.
Plants and animals
release CO2 to the
atmosphere during
cellular respiration.
CO2 CO2
When fossil fuels
are burned, CO2 is
released into the
atmosphere.
CO2
CO2
CO2
Consumers take in
carbon when they
eat plants or other
animals.
When plants and animals die,
decomposers break down
their remains, releasing CO2
into the atmosphere and soil.
After millions of
years of being
buried in the
Earth, dead plant
and animal matter
becomes fossil
fuels (oil/coal).
What are decomposers?
Organisms that break down dead plant and
animal matter.
Ex: bacteria, fungi, earthworms
Other natural ways carbon is released into
the atmosphere…
Volcanic eruptions and forest fires
Adventures of Carbon Dude
Carbon sinks
(absorbers)
Carbon sources
(releasers)
Plants
Animals
Ocean
Decomposers
Atmosphere
Volcanic activity
Soil
Deforestation
Burning fossil fuels
How humans affect
the
carbon cycle…
 Burning fossil fuels is
releasing more carbon
into the atmosphere.
 Deforestation removes
trees that absorb carbon
and the fire releases
carbon dioxide.
So, more carbon is being
released now than is being
absorbed!!
Exit Slip (carbon cycle)
1. During the carbon cycle, by which process do
producers (plants) obtain carbon from their
environment?
2. How do consumers (animals) get the carbon they
need?
3. When organisms die, what other type of organism
breaks down their remains to return carbon into
the soil and air?
Oxygen Cycle
The process by which oxygen is recycled
through ecosystems.
O2
O2
O2
Plants produce
and release
oxygen during
photosynthesis
O2
O2
O2
O2
O2
Animals take in
O2 from air or
water
The ocean also plays a BIG role in the
carbon and oxygen cycles!
There is 50 times MORE carbon in
the ocean than in the atmosphere!
Marine plants (such as algae) are responsible
for producing HALF the oxygen that we breathe!
Questions
4. Explain how the cycles work together to keep a
balance of oxygen and carbon on Earth.
Nitrogen Cycle
The process by which nitrogen is recycled
in an ecosystem.
BrainPOP: Nitrogen Cycle
“Free” nitrogen
falls to the
Earth in
precipitation
Free nitrogen is converted into a
usable form by bacteria on plant
roots in a process called nitrogen
fixation.
Decomposers return nitrogen
to the atmosphere and soil
through waste and decay.
The usable nitrogen
can now be
absorbed by the
plants
Animals get nitrogen from eating the plants or
by eating other animals that ate the plants
What is the source of
energy for all cycles in nature?
5. Describe what must happen to nitrogen gas
(“free” nitrogen) before organisms are able to use it.