Question

1. ccc systems what are the two roles of bacteria in the nitrogen cycle?

Explanation:

In the nitrogen cycle, bacteria play crucial roles. Some bacteria, like nitrogen - fixing bacteria (e.g., Rhizobium), convert atmospheric nitrogen (\(N_2\)) into ammonia (\(NH_3\)) through nitrogen fixation. This makes nitrogen available for plants. Another group is the denitrifying bacteria. They convert nitrates (\(NO_3^-\)) back into nitrogen gas (\(N_2\)), which is released into the atmosphere, thus completing the cycle.

Answer:

Bacteria in the nitrogen cycle act as nitrogen - fixers (converting \(N_2\) to \(NH_3\)) and denitrifiers (converting \(NO_3^-\) to \(N_2\)).