Question

With regard to the Biological Nitrogen Fixation by Rhizobium in association with soyabean, which one of the following statement/ statements does not hold true.

• A. Nitrogenase is Mo-Fe protein
• B. Leg-hemoglobin is a pink coloured pigment
• C. Nitrogenase helps to convert N2 gas into two molecules of ammonia
• D. Nitrogenase may require oxygen for its functioning

Answer 1

The correct option is D Nitrogenase may require oxygen for its functioning

Symbiotic association between Rhizobium and leguminous plants (soyabean)



* Rhizobium is a free-living bacteria that forms symbiotic association with leguminous plants.

* Nodules are formed in the plant at the site of infection of the bacteria.

Nitrogen-fixing enzyme

* Enzyme nitrogenase, present in Rhizobium, helps in the conversion of atmospheric nitrogen to two molecules of ammonia.

* It is Mo-Fe protein and gets inactivated in the presence of oxygen.

Leg-haemoglobin is an oxygen-scavenging pink colored protein present in the nodules that protects nitrogenase from oxygen.

Final answer

Nitrogenase may require oxygen for its functioning.