Which of the following pyrimidine base is present in $RNA$?

The difference between $DNA$ and $RNA$ is based on the presence or absence of a hydroxyl group at which carbon atom of the sugar molecule?

The number of hydrogen bonds between guanine and cytosine; and between adenine and thymine in $DNA$ is

Which of the following statements is correct?

Which of the following nitrogen bases of nucleic acids is derived from purine?

What is the relationship between nucleotide triplets and amino acids called?