Which is the first step to occur during the process of replication?

a. synthesis of leading strand on parent dna molecule
b. addition of nucleotides to the lagging strand of the growing dna molecule
c. breaking of hydrogen bonds between complementary bases of parent

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.