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Assertion: Discovery of penicillin by Al...

Assertion: Discovery of penicillin by Alexander Flemming was a serendipity.
Reason: Flemming was working on Penicillium notatum along with Staphylococcus bacteria.

A

If both Assertion and Reason are true and the Reason is the correct explanation of the Assertion

B

If both Assertion and Reason are true and the Reason is not the correct explanation of the Assertion.

C

If Assertion is true but the Reason is false.

D

If both Assertion and Reason are false.

Text Solution

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The correct Answer is:
### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that the discovery of penicillin by Alexander Fleming was a serendipity. This means that it was an accidental and fortunate discovery rather than a planned experiment. 2. **Understanding the Reason**: The reason provided is that Fleming was working on Penicillium notatum along with Staphylococcus bacteria. This suggests that he was intentionally studying both organisms. 3. **Historical Context**: In 1928, Alexander Fleming was indeed studying Staphylococcus bacteria. During his research, he noticed that a mold had contaminated one of his petri dishes, and this mold was identified as Penicillium notatum. 4. **Accidental Discovery**: Fleming observed that the mold was killing the surrounding Staphylococcus bacteria. This observation was not part of his original research plan; hence, it qualifies as a serendipitous discovery. 5. **Conclusion on Assertion and Reason**: - The assertion is true because the discovery of penicillin was indeed a serendipitous event. - The reason is false because Fleming was not actively working on Penicillium notatum; he was studying Staphylococcus bacteria and happened to discover the effects of the mold accidentally. 6. **Final Statement**: Therefore, the assertion is correct, but the reason is incorrect.
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Assertion : While working on staphylococci, Alexander Fleming observed that Penicillium notatum inhibits the growing of bacteria Reason : The inhibiting chemical was commercially extracted and its full potential was established by Alexander Fleming

Knowledge Check

  • Assertion: Lederberg's experiment explains the genetic basis of adaptations in bacteria. Reason: Certain bacterial cells become penicillin-resistant in response to penicillin.

    A
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