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9 Cards in this Set
- Front
- Back
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What is the major difference between the atmosphere 600 million years ago and today?
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There is now oxygen, co2 is in biomass. co2 was 13x higher
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What happened to cause this change?
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Plants emitted oxygen and took in co2 through photosynthesis
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What are the advantages and disadvantages of free oxygen?
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advan- humans/organisms survives off of it
dis- it was a deadly toxin to most preexisting life forms |
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How has photosynthesis altered life on earth?
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Organisms had to adapt/evolve to tolerate the oxygen due to photosyntheses
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What major fuel source did people replace when they switched to coal? What is the major advantage?
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Wood. Coal has more energy
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Why is natural gas a great source of energy?
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Cleaner than oil and coal, easy to transport.
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Why does modern history reflect the fact oil is our major source of energy
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Because we depend on the middle east for oil
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By burning coal, what are people actually doing
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Releasing energy stored in plants more than 250 million years ago. Releases co2 into atmosphere
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Describe how forests help moderate our climate
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1) Decrease temp.
2)Increase humidity 3)Decrease wind speed 4)Decrease soil erosion 5) Provides oxygen |
