Question

Bacteria that convert nitrates into free nitrogen are

• A. Ammonifying
• B. Nitrifying
• C. Denitrifying
• D. Nitrogen fixing bacteria

Answer 1

The correct option is C Denitrifying

Ammonifying bacteria are those bacteria that convert atmospheric nitrogen into ammonia. These are also called as nitrogen fixing bacteria. For example, Rhizobium, Azotobacter. Nitrifying bacteria are those bacteria that those bacteria which convert ammonia to nitrite and nitrite to nitrate. For example, Nitrosomonas, Nitrosococcus, Nitrobacter. Denitrifying bacteria are those bacteria that convert nitrates into nitrites and nitrites into free nitrogen. For example, Thiobacillus denitrificans, Micrococcus denitrificans, Pseudomonas aeruginosa.

Thus, the correct answer is 'Denitrifying.'