Question

Carefully read the following reactions carried out by nitrogen fixing bacteria. Identify the statement about these equations which is true:
$2{NH}_3+3O_2⟶2N{O}_2^{-}+2H^{+}+2H_{2}O.....\left(A\right)$
$2N{O}_2^{-}+O_2⟶2N{O}_3^{-}......\left(B\right)$

• A. Step $\left(A\right)$ is carried out by Nitrosomonas or Nitrococcus
• B. Step $\left(B\right)$ is carried out by Nitrobacter
• C. Both the steps $\left(A\right)$ and $\left(B\right)$ can be called nitrification
• D. All of the above

Answer 1

Answer: (D)

All of the above

The reactions given are the step of nitrification. This is the first step of nitrogen fixation in the nitrogen cycle. The first reaction is the conversion of ammonia to nitrite. This reaction is carried out by the Nitrosomonas and Nitrococcus. The second reaction is the conversion of the nitrite to nitrate. This reaction is carried out by Nitrobacter.

Thus, the correct answer is option D.