Question

A nitrogenous base is present in RNA but absent in DNA. Name it. Give example in which it exists.

Answer 1

In DNA, four bases have been found. They are adenine (A), guanine (G), cytosine (C) and thymine (T). The first three of these bases are found in RNA also but the fourth which is uracil (U) is absent in it.

RNA contains cytosine and uracil as pyrimidine bases while DNA has cytosine and thymine. Both have the same purine bases i.e. guanine and adenine.

Eg : UTP (uridine triphosphate).