1. Cycles of Matter
December 7th, 2012

2. Energy
Energy is crucial to an ecosystem but organisms need more than energy to survive.
95% of the body is made up of oxygen, carbon, hydrogen, and nitrogen.
These elements are common on Earth but unless the elements are in a chemical form that cells can use, organisms cannot use them.

3. Recycling
Energy and matter move through the biosphere very differently.

4. Recycling
Matter is recycled within and between ecosystems from one organism to another and from one part to another

5. 4 Cycles
Water Cycle
Nitrogen Cycle
Phosphorus Cycle
Carbon Cycle

6. Nitrogen Cycle Where is nitrogen found?
The atmosphere is the largest sink and is 78% nitrogen
The soil
In plants & animals as amino acids

7. Nitrogen Cycle
Free Nitrogen in the atmosphere must be “fixed” from a gas (N2)to a useable substance.

8. Nitrogen
The process by which nitrogen is “fixed” to a useable form is called Nitrogen Fixation.
Nitrogen fixation is a complicated process that can happen by:
bacteria in plant roots
decomposers in soil (bacteria)
lightning
forest fires.

9. Nitrogen is being “fixed”
in both of these photos

10. Nodules (clumps) of bacteria hard at work “fixing” nitrogen into plant roots…

11. OTHER SNEAKY STEPS
Animal waste
gives off nitrogen gas…
Decomposing bacteria
release nitrogen as they
breakdown dead things.

12. HOW THE NITROGEN CYCLE WORKS
Denitrification: The escape of nitrogen into the atmosphere.

14. Phosphorus Cycle Phosphorus is essential to all living organisms
Forms part of your DNA and RNA
Largest sink is the ground where it is stored in rocks and soil and released when they wear down

15. Phosphorus cycle

16. Carbon Cycle Four Processes involved:
Biological (photosynthesis and respiration)
Geochemical (volcanoes)
Mixed biogeochemical (fossil fuels)
Human activity (mining, burning fossil fuels)

17. Carbon Sinks Most of the carbon is stored underground
The largest active sink for Carbon dioxide is the oceans. They absorb most manmade carbon dioxide.
The Carbon dioxide concentration of the Earth’s atmosphere is 387 ppmv or %.

18. Carbon Cycle

20. Carbon Dioxide
Carbon will combine with oxygen to form carbon dioxide

21. Plants
Take in Carbon Dioxide (CO2) and release oxygen gas (O2) in the process of photosynthesis

22. Photosynthesis Remember that in a chemical reaction that…
Reactants → Products
In photosynthesis, carbon dioxide and water react in the presence of sunlight to form oxygen and glucose.

23. Photosynthesis The formula for photosynthesis is
Carbon dioxide + water → oxygen gas + glucose
We can balanced the equation and substitute the correct chemical symbols and it looks like…
6 CO2 + 6 H2O → 6 O2 + C6H12O6

24. Cellular Respiration How do we get the energy that our cells need?
We eat to provide energy for our cells which in turn use that energy to carry out their jobs.
When the cells “burn” glucose for energy, the process is called cellular respiration.

25. Cellular Respiration
Our cells take in oxygen and glucose from the blood stream to use as energy and produce carbon dioxide and water as products.
We can balanced the equation and substitute the correct chemical symbols and it looks like…
6 O2 + C6H12O6 → 6 CO2 + 6 H2O
Does this look familiar?

26. Paired processes
Why do you think Photosynthesis and cellular respiration are considered paired processes?
Photosynthesis
6 CO2 + 6 H2O → 6 O2 + C6H12O6
Cellular Respiration
6 O2 + C6H12O6 → 6 CO2 + 6 H2O

27. The end…