Question

Describe two parts of the nitrogen cycle where bacteria play a crucial role. Name the input, product, name of process/bacteria (if appropriate) and what uses it next.

Answer 1

Nitrogen cycle is the change from free nitrogen to fixed inorganic nitrogen ,next to organic nitrogenous compound, then again nitrogen back into atmosphere.

Two major step in nitrogen cycle is :-

1.Nitrogen fixation:- atmospheric nitrogen fixed to ammonia by microorganisms. This process done by Rhizobium sp (fix Nitrogen symbioticlly) & Azotobacter( free living nitrogen fixation)

Input:- atmospheric nitrogen (N2)

Output products:- NH4+

This NH4+ utilize by plants, and incorporate into their biomass.

2.Nitrification:-In thses step microorganisms convert ammonia to nitrate.

Responsible microorganisms:- gram negative chemoheterotrophs , Nitrosomonas nitrosus, Nitrosomonas tennis.

Input:- NH3+

Output:-HNO3

This HNO3 reduce by other microorganism and convert to gaseous Nitrogen