The function of pure lines: ?

The developed pure lines provide permanent populations allowing phenotyping of traits of the same genotypes at different times and under different environmental conditions. Both geneticists and breeders have been seeking ways to accelerate the process of pure line production.

explanation:

b,bacteria convert nitrates

into nitrogen gas.

d,plants and animals take in

and use nitrogen compounds.

e,bacteria break down waste    

products and return nitrogen  

to the soil.

a,bacteria convert atmospheric

nitrogen to ammonia.

c,bacteria convert ammonia

to nitrites and nitrates.