NTA Abhyas NEET2020BotanyMineral NutritionPractice
How many protons and electrons are required to fix a dinitrogen?
Options
- A32 each
- B8 each
- C6 each
- D4 each
Correct answer
B. 8 each
Step-by-step solution
In nitrogen-fixing microorganisms, the eight high-potential electrons come from reduced ferredoxin, generated by photosynthesis or oxidative processes. Two molecules of ATP are hydrolyzed for each electron transferred. Thus, at least 16 molecules of ATP are hydrolyzed for each molecule of N 2 reduced. 8 protons are needed for this reduction. N 2 + 8 e - + 8 H + + 16 ATP → 2 NH 3 + H 2 + 16 ADP + 16 iP