CBSE 2025 · Region 1 · Set 2 · Q14 · 1 mark
Assertion (A) : While working on Staphylococci, Alexander Fleming observed that Penicillium notatum inhibits the growth of bacteria.
Reason (R) : The inhibiting chemical was commercially extracted and its full potential was established by Alexander Fleming.
Official answer
From CBSE’s own marking scheme for this paper.
(C)
(A) is true, but (R) is false.
Microbes in Human WelfareMicrobes in Household ProductsUnderstandassertion_reasoneasy
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CBSE Class 12 Biology past-paper question from the 2025board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.