How is atmospheric nitrogen converted to a usable form in the biosphere?
A)Atmospheric nitrogen is directly available to plants and animals through the photosynthetic process and trophic relationships.
B)It is absorbed into plants via stoma and converted within the plant to a usable form.
C)Bacteria within root nodules of legumes chemically change 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.
E)Atmospheric nitrogen combines with atmospheric moisture and a free oxygen molecule to form nitric acids (HNO3),which enters in the biosphere as mildly acidic precipitation.

Question

Quizplus · Accepted Answer

Bacteria within root nodules of legumes have the unique ability to fix atmospheric nitrogen and convert it to ammonia and nitrates, which can be used by plants as a nutrient source. This process is called nitrogen fixation and is a key component of the nitrogen cycle in the biosphere. Other species of bacteria also play a role in converting atmospheric nitrogen to a usable form through processes such as nitrification and denitrification. Plant and animal cells cannot directly utilize atmospheric nitrogen, so the conversion performed by these bacteria is essential for life on Earth.

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