Gram -ve bacteria stain during gram staining____________?

Correct answer: B. Red color

  • A. Blue color
  • B. Red color
  • C. Green
  • D. Colorless

Explanation

Gram-negative bacteria lose the crystal violet-iodine complex during alcohol decolourisation because their thin peptidoglycan layer cannot retain it. They then take up the counterstain safranin and appear pink to red.

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