CBSE 2023 · Region 1 · Set 1 · Q16 · 1 mark
Assertion (A) : Birds like pigeon have heterogametic females whereas the males are homogametic.
Reason (R) : In pigeons, females have Z and W sex chromosomes whereas males have ZZ sex chromosomes.
Official answer
From CBSE’s own marking scheme for this paper.
(A)
Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
Principles of Inheritance and VariationSex DeterminationUnderstandassertion_reasonmedium
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CBSE Class 12 Biology past-paper question from the 2023board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.