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Molecular Basis of Inheritance — BIOLOGY STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceBIOLOGYMolecular Basis of Inheritance1 Mark
MCQ
For two statements are given$-$one labelled Assertion and the other labelled Reason. Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: Adenine and guanine are double $-$ ring bases.
Reason: Adenine and guanine are pyrimidines.
  • A
    Both assertion and reason are true, and reason is the correct explanation of assertion.
  • B
    Both assertion and reason are true, but reason is not the correct explanation of assertion.
  • ✓
    Assertion is true, but reason is false.
  • D
    Both assertion and reason are false.
✓

Answer

Correct option: C.
Assertion is true, but reason is false.
The bases of nucleic acids are of two types$, (i)$ pyrimidines and $(ii)$ purines. Adenine and guanine are double$-$ring bases called purines cytosine, thymine and uracil are single $-$ ring bases called pyrimidines

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