Multi-celled algae grow into larger organisms through cell division. For one-celled algae, the purpose of cell division is

the concept of nucleosome occupancy, which reflects the fraction of cells from the population in which a given region of dna is occupied by a histone octamer

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.

the answer to you question is   jet streams