Biology 2016 JAMB Past Questions - Question 34: In the nitrogen cycle, the nitrates in the soil are converted to atmospheric nitrogen by

Correct Answer

D

Explanation

Atmospheric nitrogen cannot be absorbed directly by green plants. The atmospheric nitrogen is first converted to soil nitrates through the activities of nitrogen fixing bacteria and lightening. All nitrates of metals dissolve in water including soil water. Thus, roots of plants absorb the nitrates. When animals feed  directly or indirectly on green plants, they obtain their own nitrate. When plants and animals die, their dead bodies are broken down to ammonia by putrefying bacteria. The. ammonia Is converted to nitrate by Nitrifying bacteria. The cycle continues i.e green plants absorb the nitrate Excess nitrate  not absorbed by green plants Is broken down to atmospheric nitrogen by denitrifying bacteria.