How is atmospheric nitrogen converted to a usable form in the biosphere?
A) Atmospheric nitrogen is directly available to plants and animals.
B) It is absorbed into plants via stomata and converted within the plant to a usable form.
C) Bacteria within root nodules of legumes chemically combine the atmospheric nitrogen into nitrates and ammonia.
D) Atmospheric nitrogen is completely unavailable to plants and animals and, as a result, synthetic fertilizers must be used.

Question

Quizplus · Accepted Answer

Bacteria within root nodules of legumes have the ability to convert atmospheric nitrogen into ammonium and nitrates that can be used by plants. This process is called nitrogen fixation and is an important process to allow plants to access nitrogen.

Therefore, Choice C is the correct answer, and the other options are incorrect.

How Is Atmospheric Nitrogen Converted to a Usable Form in the Biosphere