Match each term with its description. (4 points)
1.
Nitrogen fixation
2.
Assimilation
3.
Nitrogen sink
4.
Nitrification
a.
The process that converts nitrogen gas to a usable nitrogen for plants
b.
The process by which bacteria convert ammonia to nitrites and nitrates
c.
Plants absorb nitrates or ammonium ions from the soil
d.
The environments of air and water that store nitrogen compounds