Question

short note on physical nitrogen fixation

Answer 1

Biological nitrogen fixation (BNF) is the process whereby atmospheric nitrogen (N=N) is reduced to ammonia in the presence of nitrogenase. Nitrogenase is a biological catalyst found naturally only in certain microorganisms such as the symbiotic Rhizobium and Frankia, or the free-living Azospirillum and Azotobacter.

Answer 2

Nitrogen fixation is a process by which nitrogen in the air is converted into ammonia or related nitrogenous compounds. Atmospheric nitrogen, which is molecular dinitrogen, is relatively nonreactive and is metabolically useless to all but a few microorganisms.