Q. Consider the following statements: Biological Nitrogen Fixation occurs in absence of Oxygen only Only Symbiotic Bacteria can fix atmospheric Nitrogen Which among the above statements is / are correct?
Answer: Both are incorrect
Notes:

1. Biological Nitrogen Fixation occurs in absence of Oxygen only - Incorrect. Both aerobic (requiring oxygen) and anaerobic (not requiring oxygen) bacteria can fix atmospheric nitrogen.
2. Only Symbiotic Bacteria can fix atmospheric Nitrogen - Incorrect. Apart from symbiotic bacteria, free-living bacteria like Azotobacter can also fix atmospheric nitrogen.

To summarize:

1. Nitrogen fixation can occur in both presence and absence of oxygen.
2. Both symbiotic bacteria and some free-living bacteria have nitrogen fixing capability.

Therefore, both statement 1 and statement 2 are incorrect.

2

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