JEE Main · 2006 · 30 Apr 2006 · Offline · Biomolecules

The pyrimidine bases present in DNA are

(A)cytosine and adenine
(B)cytosine and guanine
(C)cytosine and thymine✓ Correct
(D)cytosine and uracil

Answer: (C)

Solution

The nitrogenous bases of DNA are two purines, adenine and guanine, and two pyrimidines. Of the pyrimidines, cytosine is common to both nucleic acids while thymine is the one specific to DNA; uracil takes its place only in RNA. The pyrimidine bases of DNA are therefore cytosine and thymine.

JEE Main · 2006 · 30 Apr 2006 · Offline · Single correct option

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