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

Which part of $DNA$ acts as a messenger for the synthesis of proteins?

If on a strand of $DNA$ the base sequence is $ATTGACGCAT$ then the sequence transcription on $RNA$ would be

When $RNA$ is hydrolysed,there is no relationship among the quantities of different bases obtained. What does this fact suggest about the structure of $RNA$?

$RNA$ and $DNA$ are chiral molecules, their chirality is due to

What is the unit of base-sugar-phosphate in nucleic acids called?