CBSE 2026 · Region 1 · Set 3 · Q10 · 1 mark
A DNA molecule is $\displaystyle 140$ base pairs long. It has $\displaystyle 20 \%$ thymine. How many guanine bases are present in the molecule?
Official answer
From CBSE’s own marking scheme for this paper.
(B)
$\displaystyle 84$
Molecular Basis of InheritanceThe DNAApplymcqeasy
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CBSE Class 12 Biology past-paper question from the 2026board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.