The ara operon is an inducible operon that controls the production of the sugar arabinose. when arabinose is present in a bacterium it binds to the protein arac, and the complex binds to the initiator site to promote transcription. in this scenario, arac is a(n)
activator
inducer
repressor
operator

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.