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Leguminous plants are able to fix atmospheric nitrogen through the process of symbiotic nitrogen fixation. Which one of the following statement is not correct during the process of nitrogen fixation?

  • Leghaemoglobin scavenges oxygen and is pinkish in colour

  • Nodules act as a site for nitrogen fixation

  • The enzyme nitrogenase catalyse the conversion of atmospheric N2 to NH3

  • Nitrogenase is insensitive to oxygen

Answer

D.

Nitrogenase is insensitive to oxygen

Root nodules of leguminous plants harbour symbiotic bacteria, Rhizobium, which fixes atmospheric nitrogen and provides the plant with most or all of its nitrogen requirements. In return, they have access to a rich supply of carbohydrate. The fixation of atmospheric nitrogen (N2) to ammonia (NH3) occurs within the nodules, using the enzyme nitrogen cut this enzyme is very sensitive to oxygen and gets inhibited in oxygen rich environment. This problem is solved by leghaemoglobin, a pinkish-red, oxygen-binding, iron-containing protein present in root nodules. It functions as oxygen buffer, scavenges oxygen and provides the enzyme nitrogenase, a low oxygen environment in which nitrogen fixation can occur.

Root nodules of leguminous plants harbour symbiotic bacteria, Rhizobium, which fixes atmospheric nitrogen and provides the plant with most or all of its nitrogen requirements. In return, they have access to a rich supply of carbohydrate. The fixation of atmospheric nitrogen (N2) to ammonia (NH3) occurs within the nodules, using the enzyme nitrogen cut this enzyme is very sensitive to oxygen and gets inhibited in oxygen rich environment. This problem is solved by leghaemoglobin, a pinkish-red, oxygen-binding, iron-containing protein present in root nodules. It functions as oxygen buffer, scavenges oxygen and provides the enzyme nitrogenase, a low oxygen environment in which nitrogen fixation can occur.