Q. Nitrite is changed to nitrate by :
(a) Nitrobacter
(b) Nitrosomonas
(c) Pseudomonas
(d) Clostridium
Solution :
Correct option : A There are two steps in nitrification process by which ammonia is converted into nitrite and nitrite into nitrate. The bacteria that convert ammonia to nitrites include Nitrosomonas, Nitrosospira and the bacteria that convert nitrites to nitrates include Nitrobacter, Nitrospina. Thus, the correct answer is ‘Nitrobacter.’
