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Home Q & A Board Biology-Related Homework Help General Biology
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Groanier Groanier
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6 years ago
The primitive Earth's atmosphere did NOT contain
 
  a. free oxygen.
  b. free nitrogen.
  c. free hydrogen.
  d. water vapor.
  e. inert gases.

Question 2

The metabolic reactions that occur in all cells require a certain molecule that was also believed to be present very early on Earth. What is this molecule?
 
  a. nitrogen
  b. carbon
  c. water
  d. oxygen
  e. hydrocarbon
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kzabeckzabec
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6 years ago
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Groanier Author
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#2
6 years ago
Oh god, I was lost before coming here. Thanksss
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#3
6 years ago
Great, make sure you mark the topic solved, it hides it from other eyes Slight Smile
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