Answer:
Role of organisms in the nitrogen cycle:
Bacteria play a central role: Nitrogen-fixing bacteria, which convert atmospheric nitrogen to nitrates. Bacteria of decay, which convert decaying nitrogen waste to ammonia. Nitrifying bacteria, which convert ammonia to nitrates/nitrites.
Explanation:
I THINK THIS IS SHORT AND EASY
Here are some that u can choose from:
1.gas filled cars
2.factory's
3.people putting stuff in lakes,pond etc.
4.buildings
