FINAL 01 - Gram Staining Flashcards
Bacteria are slightly negatively charged at pH __________
pH 7.0
__________ dye stains bacteria
Basic dye
__________ dye stains background
Acidic dye
Refers to an aqueous or alcohol solution of single basic dye
Simple stin
Is a substance that adheres to a cell, giving the cell color
Stain
Is an auxiliary technique used in microscopy to enhance contrast in the microscopic image
Staining
Single dye is used to color or highlight the entire organism (Types of staining techniques)
Simple staining
Distinguish bacteria according to their reaction to particular stains (Types of staining techniques)
Differential staining
Used to color specific parts or structures of a microorganism (Types of staining techniques)
Special/structural staining
Process that aims to preserve the shape of the cells or tissue involves as much as possible
Fixation
Is used to determine gram status to classify bacteria broadly
Gram staining
Gram staining is named after __________
Gram staining
Stain that acts as the primary stain
Crystal violet
Stain that acts as a mordant (helps to fix the primary dye to the cell wall)
Gram’s iodine
Is used to remove the primary stain; is usually composed of an organic solvent
Decolorizer
A counterstain that is applied to stain those cells that have lost the primary stain as a result of decolorization
Safranin
2 types of stains (GA)
Gram stain, Acid-fast stain
Refers to bacteria that are stained dark blue or violet by gram staining
Gram-positive bacteria
__________, also called murein, are heteropolymers of glycan strands, which are cross-linked through short peptides
Peptidoglycans
Refers to bacteria that appear red or pink because they are counterstained
Gram-negative bacteria
Are acid-fast, gram-resistant, non-motile, pleomorphic rods related to Actinomyces; most are found in water and soil
Mycobacterium
Mycobacterium species that is pathogenic for humans
Mycobacterium tuberculosis
Mycobacterium species that is pathogenic for animals
Mycobacterium bovis
Acid bast fells contain a large amount of lipids and waxes in their cell walls, primarily __________
Mycolic acid
Acid fast bacteria are usually members of the genus __________ or __________ (MN)
Mycobacterium, Nocardia
Used to stain species of Mycobacterium tuberculosis that do not stain within the laboratory staining procedures like gram staining
Ziehl-Neelsen staining
In Ziehl-Neelsen staining, the stains used are the red colored __________ that stains the bacteria and a counter stain like Methylene blue or Malachite green
Carbol fuchsin
In Ziehl-Neelsen staining, the stains used are the red colored Carbol fuchin that stains the bacteria and a counter stain like __________ or _________ (MM)
Methylene blue, Malachite green
A lipid soluble, phenolic compound which is able to penetrate the cell wall; used in Ziehl-Neelsen staining
Carbol fuchsin
__________ are less acid fast than Mycobacterium tuberculosis
Mycobacterium leprae
When staining Mycobacterium leprae, the concentration of H2SO4 is reduced to __________ for decolorizing
5%
Used to reveal flagella (Types of special staining)
Flagellar staining
2 microorganisms that utilize flagellar staining (VS)
Vibrio cholerae, Spirillum
Used to reveal endospores (Types of special staining)
Endospore staining
2 microorganisms that utilize endospore staining (BC)
Bacillus, Clostridium
Used to reveal negatively charged bacterial capsules (Types of special staining)
Capsule staining
2 stains used in negative staining technique (IN)
India ink, Nigrosin
In __________, organisms are not stained, only the background is stained
Negative staining
Negative staining is used to demonstrate the capsule of __________ and __________ (CS)
Cryptococcus neoformans, Streptococcus pneumoniae
