Which of the following is not a pyrimidine nitrogenous base?

The percentage of nucleic acids in an animal cell is approximately ...... . (in $\%$)

Which of the following is a structural component of nucleic acid?

$P$: Nitrogen is essential for the synthesis of nucleic acids.
$Q$: Phosphorus is important in the structure of nucleic acids.

Which of the following is $NOT$ present in the structure of a nitrogenous base?

The structure of a nucleotide is given below. Identify the bonds $P$ and $Q$.
$P \quad \quad Q$