Question

Some bacteria live in the roots of plants like soy beans and peas.
What is the role of these bacteria in the nitrogen cycle?

1.To absorb nitrogen containing compounds from the soil
2. To release free nitrogen into the atmosphere.
3. To breakdown nitrogen containing compounds in dead organisms.
4.To convert three nitrogen into usable nitrogen

Answer 1

1. Nitrifying bacteria in the soil convert ammonia into nitrite (NO2-) and then into nitrate (NO3-). This process is called nitrification. Compounds such as nitrate, nitrite, ammonia and ammonium can be taken up from soils by plants and then used in the formation of plant and animal proteins.
2. Prokaryotes play several roles in the nitrogen cycle. Nitrogen-fixing bacteria in the soil and within the root nodules of some plants convert nitrogen gas in the atmosphere to ammonia. Nitrifying bacteria convert ammonia to nitrites or nitrates.
3. A wide range of soil fungi and bacteria, called the decomposers, carry out the ammonification process. The decomposers consume the organic matter, and the nitrogen contained in the dead organism is converted to ammonium ions. The ammonium is then converted to nitrates by the nitrifying bacteria.
4. Nitrogen-fixing bacteria in the soil and within the root nodules of some plants convert nitrogen gas in the atmosphere to ammonia. Nitrifying bacteria convert ammonia to nitrites or nitrates. Ammonia, nitrites, and nitrates are all fixed nitrogen and can be absorbed by plants.