Question

1. what is the role of bacteria in the nitrogen cycle? 7. nitrifying bacteria convert nitrites into ______ 8. if the denitrifying bacteria was removed from the cycle what would happen to the nitrogen cycle? nitrogen in atmosphere (n₂) plants assimilation decomposers (aerobic and anaerobic bacteria and fungi) ammonification ammonium (nh₄⁺) nitrification nitrites (no₂⁻) nitrifying bacteria nitrates (no₃⁻) denitrifying bacteria nitrogen - fixing bacteria in root nodules of legumes

Explanation:

Question 6: What is the role of bacteria in the nitrogen cycle?

Bacteria have multiple roles: Nitrogen - fixing bacteria (e.g., in legume roots) convert atmospheric \(N_2\) to ammonia/ammonium for plants. Ammonifying bacteria (decomposers) break down organic matter into ammonium. Nitrifying bacteria convert ammonium to nitrites (\(NO_2^-\)) and then nitrites to nitrates (\(NO_3^-\)). Denitrifying bacteria convert nitrates back to atmospheric \(N_2\), completing the cycle.

From the nitrogen cycle diagram and knowledge, nitrifying bacteria (specifically the second group of nitrifying bacteria) take nitrites (\(NO_2^-\)) and convert them into nitrates (\(NO_3^-\)) during the nitrification process.

Denitrifying bacteria's role is to convert nitrates (\(NO_3^-\)) back to atmospheric nitrogen (\(N_2\)). If they are removed, the nitrates in the soil and water would not be converted back to \(N_2\). So, the amount of nitrates in the ecosystem would accumulate over time as there is no process to return the nitrogen from the nitrate form back to the atmosphere. This would disrupt the balance of the nitrogen cycle, as the nitrogen that is taken up by plants (in the form of nitrates) and then passed through the food web would not be recycled back to the atmosphere, leading to a build - up of nitrates in the soil and water, and a decrease in the amount of nitrogen available in the atmosphere for nitrogen - fixing bacteria to use in the long run (as the cycle is disrupted).

Answer:

Bacteria perform nitrogen - fixing (convert \(N_2\) to usable forms for plants), ammonification (break down organic matter to ammonium), nitrification (convert ammonium to nitrites and nitrates), and denitrification (convert nitrates to \(N_2\) to return to atmosphere) in the nitrogen cycle.

Question 7: Nitrifying bacteria convert nitrites into ______