Question

During nitrogen fixation, ammonia is first oxidized to nitrite which is further oxidized to nitrate and the reactions are given below

2NH3+302 → 2NO2-+ 2H+ +2H20.....(i)

2NO2-+02→ 2NO3- ......(ii)

The reaction (i) is facilitated by the action of:

• A. Nitrosomonas
• B. Nitrococcus
• C. Nitrosomonas and/or Nitrococcus
• D. Nitrobacter

Answer 1

Answer:

C. Nitrosomonas and/or Nitrococcus

• The process of conversion of nitrogen to ammonia is called nitrogen fixation.

• First ammonia is oxidized to nitrate by the bacteria Nitrosomonas/ Nitrococcus.

• Then nitrate is converted to nitrite by the bacteria Nitrobacter.

• These bacteria are chemoautotrophs.