1. What goes around comes back around!
Water Cycle, Carbon Cycle, Oxygen Cycle & Nitrogen Cycle

2. Water Cycle
The water cycle involves the processes of evaporation, condensation, precipitation, transpiration, percolation and runoff.
BrainPOP: Water Cycle

3. Percolation

4. BrainPOP: Carbon Cycle
The process by which carbon moves between organisms and their physical environment.
BrainPOP: Carbon Cycle

5. When fossil fuels are burned, CO2 is released into the atmosphere.
Plants and animals release CO2 to the atmosphere during cellular respiration.
When fossil fuels are burned, CO2 is released into the atmosphere.
Producers take in CO2 during photosynthesis.
CO2
CO2
After millions of years of being buried in the Earth, dead plant and animal matter becomes fossil fuels (oil/coal).
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.

6. What are decomposers?
Organisms that break down dead plant and animal matter.
Ex: bacteria, fungi, earthworms

7. Adventures of Carbon Dude
Other natural ways carbon is released into the atmosphere…
Volcanic eruptions and forest fires
Adventures of Carbon Dude

8. Carbon sinks (absorbers)
Carbon sources (releasers)
Plants
Ocean
Atmosphere
Soil
Animals
Decomposers
Volcanic activity
Deforestation
Burning fossil fuels

9. 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!!

11. Exit Slip (carbon cycle)
During the carbon cycle, by which process do producers (plants) obtain carbon from their environment?
How do consumers (animals) get the carbon they need?
When organisms die, what other type of organism breaks down their remains to return carbon into the soil and air?

12. Oxygen Cycle
The process by which oxygen is recycled through ecosystems.

13. O2 O2 O2 O2 O2 O2 O2 O2
Plants produce and release oxygen during photosynthesis
Animals take in O2 from air or water

14. 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!

15. Questions
4. Explain how the cycles work together to keep a balance of oxygen and carbon on Earth.

16. BrainPOP: Nitrogen Cycle
The process by which nitrogen is recycled in an ecosystem.
BrainPOP: Nitrogen Cycle

17. “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.
The usable nitrogen can now be absorbed by the plants
Decomposers return nitrogen to the atmosphere and soil through waste and decay.
Animals get nitrogen from eating the plants or by eating other animals that ate the plants

18. What is the source of energy for all cycles in nature?
THE SUN!

19. Describe what must happen to nitrogen gas
(“free” nitrogen) before organisms are able to use it.