Which process is the conversion of ammonia to nitrites and then nitrates?

Which process is the conversion of ammonia to nitrites and then nitrates?

• A. Ammonification
• B. Denitrification
• C. Nitrification
• D. Nitrogen fixation

Answer: (C)

Nitrification is the microbial oxidation of ammonia first to nitrite and then to nitrate. In well‑aerated environments, ammonia-oxidizing bacteria convert NH3/NH4+ to NO2−, and nitrite-oxidizing bacteria then convert NO2− to NO3−. This two‑step process provides energy for the involved bacteria and is a key part of how nitrogen moves through ecosystems. Ammonification releases ammonia from organic nitrogen, denitrification reduces nitrate to nitrogen gas under low oxygen, and nitrogen fixation converts atmospheric N2 into ammonia, so the described conversion specifically matches nitrification.

Nitrification is the microbial oxidation of ammonia first to nitrite and then to nitrate. In well‑aerated environments, ammonia-oxidizing bacteria convert NH3/NH4+ to NO2−, and nitrite-oxidizing bacteria then convert NO2− to NO3−. This two‑step process provides energy for the involved bacteria and is a key part of how nitrogen moves through ecosystems. Ammonification releases ammonia from organic nitrogen, denitrification reduces nitrate to nitrogen gas under low oxygen, and nitrogen fixation converts atmospheric N2 into ammonia, so the described conversion specifically matches nitrification.