Which of the following mineral elements play an important role in biological nitrogen fixation?
Show Hint
• Nitrogenase = Fe + Mo
• Mo is essential for N$_2$ fixation
- Copper
- Magnesium
- Molybdenum
- Zinc
The Correct Option is C
Solution and Explanation
• Nitrogenase contains a Fe-Mo cofactor (iron–molybdenum)
• Molybdenum is essential for enzyme activity
Step 1: Analyzing each option.
• Copper: Not directly involved in nitrogen fixation → Incorrect.
• Magnesium: Important for enzymes but not nitrogenase → Incorrect.
• Molybdenum: Essential component of nitrogenase → Correct.
• Zinc: Cofactor for many enzymes but not nitrogen fixation → Incorrect.
Step 2: Selecting the correct answer.
Thus, molybdenum plays a key role in biological nitrogen fixation.
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