Which group of soil microorganisms converts atmospheric nitrogen into nitrogenous compounds usable by plants?
Answer and explanation
Correct answer: A. Nitrogen-fixing bacteria (e.g. Rhizobium)
- Step 1: Nitrogen-fixing bacteria such as Rhizobium in legume root nodules capture inert atmospheric N2 gas. Step 2. They convert elemental nitrogen into ammonium and nitrates that host plants can absorb. Answer: Nitrogen-fixing bacteria (e.g. Rhizobium). Why not the others: Denitrifying bacteria return nitrogen to the atmosphere; nitrifying bacteria convert ammonia to nitrates; fungi decompose dead matter.
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