A Major Constituent of Earth's Atmosphere Is Nitrogen Gas (N₂)

Multiple Choice

A major constituent of Earth's atmosphere is nitrogen gas (N₂) , which makes up 79% of the air we breathe. Primary producers such as plants and algae cannot assimilate this form of nitrogen into biomolecules. Instead they rely on Bacteria and Archaea to convert N₂ to ammonia (NH₃) . This important biological reaction is called:

A) denitrification.
B) nitrification.
C) nitrogen fixation.
D) anammox.