NURSING EXAM QUESTIONS
MICROBIOLOGY
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Cell wall
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Ribosomes
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Inclusions
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Flagella
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Detailed explanation-1: -The basic principle of gram staining involves the ability of the bacterial cell wall to retain the crystal violet dye during solvent treatment. Gram-positive microorganisms have higher peptidoglycan content, whereas gram-negative organisms have higher lipid content.
Detailed explanation-2: -What is Gram Staining? Gram staining is a common technique used to differentiate two large groups of bacteria based on their different cell wall constituents. The Gram stain procedure distinguishes between Gram positive and Gram negative groups by coloring these cells red or violet.
Detailed explanation-3: -Gram’s staining method is considered fundamental in bacterial taxonomy. The outcome of the Gram reaction reflects major differences in the chemical composition and ultrastructure of bacterial cell walls.
Detailed explanation-4: -Gram-positive bacteria have cell walls that contain thick layers of peptidoglycan, a substance that forms the cell walls of many bacteria. The peptidoglycan forms about 90% of the cell wall in gram-positive bacteria. This causes them to appear blue to purple under a Gram stain.
Detailed explanation-5: -The gram-positive bacteria retain the crystal violet colour and stain purple whereas the gram-negative bacteria lose crystal violet and stain red. Thus, the two types of bacteria are distinguished by gram staining. Gram-negative bacteria are more resistant to antibodies because their cell wall is impenetrable.