Why is diagnosing a parasite infection difficult? What factors make it challenging?

The difficulty in developing vaccines against parasitic diseases is to identify (and produce) appropriate protective antigens because of the lack of complete understanding of the type of immune response required for protection.

Explanation:

I hope this kinda helps.

true is the answer : )

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.