Biological Nitrogen Fixation Is Energetically Expensive

question 23

Multiple Choice

Biological nitrogen fixation is energetically expensive. Assuming that NADPH is used as the reducing equivalent, how many ATPs are used in the enzymatic conversion of N₂ to NH₃?

• A) 16
• B) 32
• C) 48
• D) 64
• E) none; only GTP is used

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