Q.43 Given below are two statements : One is labelled as Assertion (A) and the other is labelled as
Reason (R).
Assertion (A) :Staphylococcus au/eus is gram negative bacteria.
Reasons (R) :Saccharomyces cerevisiae and Neurospora crassa are the examples of class
Ascomycetes in fungi.
In the light of the above statements, choose the most appropriate answer from the options given
below :
(1)Both (A) and (R) are correct and (R) is the correct explanation of (A)
(2)Both (A) and (R) are correct but (R) is NOT the correct explanation of (A)
(3)(A) is correct but (R) is not correct
(4)(A) is not correct but (R) is correct
Staphylococcus Aureus Gram Stain and Ascomycetes Examples: Assertion-Reason Solved
Staphylococcus aureus is a Gram-positive bacterium, not Gram-negative as stated in (A), while Saccharomyces cerevisiae and Neurospora crassa are correctly examples of Ascomycetes class in fungi.
The correct option is (4): (A) is false, but (R) is true.
Question Breakdown
Assertion (A) incorrectly claims Staphylococcus aureus (likely “aureus,” with “au/eus” as a typo) is Gram-negative; it is Gram-positive cocci in clusters, forming a thick peptidoglycan layer that retains crystal violet stain.
Reason (R) is accurate: Both Saccharomyces cerevisiae (yeast) and Neurospora crassa (filamentous mold) belong to Ascomycota phylum, class Ascomycetes, producing ascospores in asci.
(R) unrelated to (A), as one concerns bacteria classification and the other fungal taxonomy.
Option Analysis
-
Option (1): Incorrect—(A) false, so (R) cannot explain it.
-
Option (2): Incorrect—(A) false despite (R) true; no explanatory link.
-
Option (3): Incorrect—(R) true for Ascomycetes examples.
-
Option (4): Correct—(A) wrong on Gram stain, (R) right on fungal classification.
Key Classifications
| Organism | Group | Gram Stain/Details |
|---|---|---|
| Staphylococcus aureus | Bacteria (Firmicutes) | Gram-positive cocci in clusters |
| Saccharomyces cerevisiae | Fungi (Ascomycota) | Yeast, Ascomycetes class |
| Neurospora crassa | Fungi (Ascomycota) | Filamentous, Ascomycetes class |
