Which bacteria convert ammonium ions to nitrite and then nitrate in the soil?
Answer and explanation
Correct answer: A. Nitrifying bacteria, in an oxidation process
- Step 1: Nitrification is the oxidation of ammonium to nitrite (Nitrosomonas) and then nitrate (Nitrobacter). Step 2. Plants then absorb nitrate. Answer: Nitrifying bacteria, in an oxidation process. Why not the others: nitrogen fixation converts N2 to ammonia; denitrification returns N2 to the air under anaerobic conditions; ammonification produces ammonium.
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