Immunity that results from exposure to an antigen in the environment is called immunity.

adaptive immunity

Explanation:

Adaptive immunity is also called as an acquired immunity as it is acquired only after interaction with an antigen. When an antigen in the form of pathogen or immunity vaccination enters into the body of an individual then the immunity system creates antibodies (which causes phagocytosis of pathogens) against the antigens and also develops a memory to fight with such foreign agents in future. The adaptive immunity is dealt by T and B cells and antibodies.  

by drinking easy

very easy

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.