Name two biologically important compounds in which nitrogen is present.

(N/A) Two biologically important compounds containing nitrogen are:
$1$. Proteins: These are complex organic molecules made up of amino acids,which contain nitrogen in their amino group $(-NH_2)$.
$2$. Nucleic Acids ($DNA$ and $RNA$): These are the genetic materials of living organisms,and their nitrogenous bases (adenine,guanine,cytosine,thymine,and uracil) contain nitrogen.