1. 9-3 Cycles of Matter-Oxygen and Carbon
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2. 6CO2 + 6 H2O C6H12O6 + 6 O2 Carbon and oxygen are recycled.
The Carbon and Oxygen Cycles
Carbon and oxygen are recycled.
Producers, consumers and decomposers all play a role in this cycle.
6CO2 + 6 H2O C6H12O6 + 6 O2
Producers (autotrophs) and Consumers (heterotrophs) are dependent on each other!

3. The Carbon Cycle
Producers take in carbon dioxide and give off oxygen. (opposite of consumers) Consumers eat producers (taking in carbon-food molecules) and release them as carbon dioxide and carbon waste products. Decomposers (worms, bacteria, etc) break down the remains of producers and consumers and return it to the soil. They also release carbon dioxide.

4. The Oxygen Cycle
Producers take in carbon dioxide and give off oxygen. (consumers are opposite) Most organisms take in oxygen and give off carbon dioxide.

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Comparing Photosynthesis and Cellular Respiration
Comparing Photosynthesis and Cellular Respiration
The energy flows in photosynthesis and cellular respiration take place in opposite directions.
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6. On a global level, photosynthesis and cellular respiration are also opposites.
Photosynthesis removes carbon dioxide from the atmosphere and cellular respiration puts it back.
Photosynthesis releases oxygen into the atmosphere and cellular respiration uses that oxygen to release energy from food.

7. The Human Impact
Humans affect the amount of carbon dioxide in the atmosphere:
Burning oil and other fossil fuels
Clearing forests for lumber
Burning down trees to clear a forest
Factories give off carbon dioxide

8. Carbon (purple) and Oxygen (orange) Cycle

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A feedback loop is a biological occurrence wherein the output of a system amplifies the system (positive feedback) or inhibits the system (negative feedback). Feedback loops are important because they allow living organisms to maintain homeostasis.
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10. Output Tasks: 1. Draw out your own version of the carbon cycle.
2. What would be the effect of the following on the amount of oxygen in the atmosphere?
an increase in the number of plants.
an increase in the burning of fossil fuels.
an increase in the number of animals.
3. How many ways can you think of increasing the amount of carbon dioxide in the atmosphere? List them.

11. END OF SECTION