Question

If by radiation all nitrogenase enzyme are inactivated, then there will be no

• A. Conversion from ammonium to nitrate in soil.
• B. Fixation of nitrogen by legumes.
• C. Conversion from nitrate to nitrite in legumes.
• D. None of the above.

Answer 1

The correct option is B Fixation of nitrogen by legumes.

Nitrogen fixation is a process in which nitrogen in the atmosphere is converted into ammonium or nitrogen oxide. Biological nitrogen fixation includes conversion to nitrogen dioxide. The biological nitrogen fixation is done with the help of nitrogenase enzymes which contain iron, molybdenum, or vanadium and are found in bacteria, blue green algae which live in symbiosis with legumes.
Plants cannot extract nitrogen directly from the atmosphere. N${}_2$ must be fixed by these bacteria as NH${}_3$. Inactivation of nitrogenase enzymes by radiation there would therefore, restrict the nitrogen fixation process by legumes.