The conversion of ammonia (NH3) to nitrites (NO2-) and then to nitrates (NO3-) by bacteria is called: MCQ with Answer and Explanation

The conversion of ammonia (NH3) to nitrites (NO2-) and then to nitrates (NO3-) by bacteria is called:
A. Ammonification
B. Nitrogen fixation
C. Nitrification
D. Denitrification
Answer: Option C
Solution (By JKExamLibrary)
Nitrification is a two-step process in the nitrogen cycle where ammonia is oxidized to nitrates. First, ammonia (NH3) is converted to nitrites (NO2-) by bacteria like Nitrosomonas. Then, nitrites are converted to nitrates (NO3-) by bacteria like Nitrobacter. Nitrates are the primary form of nitrogen absorbed by plants. Denitrification is the reverse process, converting nitrates back to nitrogen gas.

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