Skip to main content
Indietro

STAINING

I pulsanti di controllo sono stati cambiati in modalità "navigazione".
1/20
  • Purpose of bacterial staining

    Staining is used to visualize bacteria, which are small and colorless, to study their properties and aid in identification.
  • Simple staining

    Uses one stain to visualize bacterial shape and arrangement.
  • Differential staining

    Uses two or more stains to differentiate bacterial species or structures.
  • Examples of differential stains

    Gram stain, acid fast stain, capsule stain, and spore stain.
  • Gram stain primary stain

    Crystal violet stains all cells purple initially.
  • Gram stain mordant

    Iodine increases cells' affinity for crystal violet, forming a complex.
  • Gram stain decolorizer

    95% ethanol dissolves lipids, increasing cell wall porosity and removing stain from some cells.
  • Gram stain counterstain

    Safranin stains cells that lost the primary stain pink.
  • Gram positive bacteria cell wall

    Thick peptidoglycan layer retains crystal violet-iodine complex, staining cells purple.
  • Gram negative bacteria cell wall

    Thin peptidoglycan and outer membrane lose crystal violet during decolorization, staining pink with safranin.
  • Common shapes of bacteria

    Coccus (round), bacillus (rod), and spiral (vibrio, spirillum, spirochete).
  • Acid fast stain primary stain

    Carbol fuchsin stains acid fast bacteria red by penetrating waxy mycolic acid cell walls.
  • Acid fast stain decolorizer

    Acid alcohol removes stain from non-acid fast cells.
  • Acid fast stain counterstain

    Methylene blue stains non-acid fast bacteria blue.
  • Acid fast bacteria examples

    Mycobacterium tuberculosis and Mycobacterium leprae.
  • Spore stain primary stain

    Malachite green stains spores.
  • Spore stain decolorizer

    Water removes stain from vegetative cells.
  • Spore stain counterstain

    Safranin stains vegetative cells pink.
  • Capsule stain technique

    Negative staining with dyes like nigrosin stains background, leaving capsules unstained and visible.
  • Purpose of capsule stain

    Visualizes gelatinous outer layer protecting bacteria from host immune cells.