Nitrifying bacteria

Options

A. convert free nitrogen to nitrogen compounds
B. convert proteins into ammonia
C. reduce nitrates to free nitrogen
D. oxidise ammonia to nitrates

Answer

D

Explanation

Nitrifying bacteria (one of the chemosynthetic bacteria) which oxidise ammonia to nitrites and obtain energy for the preparation of food. This obtain energy for the preparation of food. This oxidation occurs in two steps. In the first step, ammonia is oxidised to nitrite by nitrite bacteria (e.g. Nitrosomonas and Nitrococcus). In the second step, nitrite is oxidised to nitrate by nitrate bacteria (e.g. Nitrocystic and nitrobacter).