Q. Function of leghaemoglobin during biological nitrogen fixation in root nodules of legumes is to :
(a) Convert atmospheric nitrogen to ammonia
(b) Convert ammonia to nitrate
(c) Transport oxygen for activity of nitrogenase
(d) Protect nitrogenase from oxygen
Solution :
Correct option : D Root nodules of a leguminous plant contain all the biochemical components required for nitrogen fixation including enzymes nitrogenase and a pink-coloured pigment called leghaemoglobin. Nitrogenase is highly sensitive enzyme to molecular oxygen as it functions under anaerobic conditions. To protect this enzyme from oxygen leghaemoglobin act as an oxygen scavenger. So the correct answer is ‘Protect nitrogenase from oxygen’.
