Question

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

• A. Leghaemoglobin scavenges oxygen and is pinkish in colour
• B. Nodules acts as site for nitrogen fixation
• C. The enzyme nitrogenise catalyses the conversion of atmospheric N₂ to NH₃
• D. Nitrogenase is insensitive to oxygen.

Answer 1

The correct option is D

Nitrogenase is insensitive to oxygen.

Nitrogenase is rapidly destroyed by oxygen,in vitroandin vivo, so nitrogen-fixing organisms face the problem of protecting their nitrogenase from inactivation by oxygen. The need to protect nitrogenase becomes particularly important in the cyanobacteria, which evolve oxygen photosynthetically.