The bacteria which convert $NO_3^- \rightarrow$ free $N_2$ are called as:

What is the function of $Pseudomonas$ and $Thiobacillus$ in the $N_2$ cycle?

$NO_2^- \rightarrow NO_3^-$
The above mentioned reaction occurs in the presence of .....

Which of the following bacteria are responsible for the process of denitrification?

What is the process of conversion of $NH_3$ to $NO_3^-$ by microorganisms called?

The process of conversion of nitrogen gas into ammonia is called $P$,and the process of decomposition of organic nitrogen in plants and animals into ammonia is called $Q$.