Question

which best compares the roles of nitrogen - fixing bacteria and certain decomposers in the nitrogen cycle?
both organisms convert free nitrogen into nitrogen - containing compounds.
both organisms convert nitrogen - containing compounds into free nitrogen.
the bacteria convert free nitrogen into nitrogen - containing compounds, while the decomposers convert nitrogen - containing compounds into free nitrogen.
the bacteria convert nitrogen - containing compounds into free nitrogen, while the decomposers convert free nitrogen into nitrogen - containing compounds.

Explanation:

Nitrogen - fixing bacteria take free nitrogen (\(N_2\)) from the atmosphere and convert it into nitrogen - containing compounds (like ammonia \(NH_3\)) through nitrogen fixation. Decomposers break down nitrogen - containing compounds (such as proteins in dead organisms) and release free nitrogen back into the environment through processes like ammonification and denitrification.

Answer:

The bacteria convert free nitrogen into nitrogen - containing compounds, while the decomposers convert nitrogen - containing compounds into free nitrogen.