Lesson eLearning

Which nitrogenous base is present only in RNA and not in DNA?

easy 1 mark Class 12 · Biology · Molecular Basis of Inheritance
Answer
Uracil

The correct answer is Uracil — Hence, uracil is the answer.

Step-by-step solution

  1. List the four DNA bases: adenine, guanine, cytosine, thymine.
  2. List the four RNA bases: adenine, guanine, cytosine, uracil.
  3. Compare the two lists to find the base present only in RNA.
  4. The unique base in RNA is uracil.
  5. Hence, uracil is the answer.
Common mistake: Confusing uracil with thymine

Concept tested: RNA‑DNA base difference

Published · How this solution was prepared and checked

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