Principles of Staining Flashcards
Colors and contrast of microorganisms in their natural state?
Colorless and lacking of contrast
An auxiliary technique used in microscopy to enhance contrast in the microscopic image.
Staining
Frequently used in biology and medicine to highlight structures in biological tissues for viewing, often with the aid of different microscopes.
Stains and dyes
The process of fixing the microorganism, or killing it, before attaching them to the slide
Fixation
Ways of fixation
Heat-fixing, air-drying, and chemical fixation
Procedure of Simple Staining
Smear microbes to slide -> air-dry -> drip methanol onto specimen to fix -> flood slide with stain -> rinse with water before blotting dry -> examine with x100 objective (OIO)
Type of staining that uses two or more dyes, as well as reacting differently with different microorganisms
Differential staining
Purpose of differential staining
To contrast two or more organisms which maybe of the same or different species
Who developed the Gram Stain
Hans Christian Gram
When was Gram Stain developed?
1884
(Gram Stain Reagent) Primary Stain
Crystal Violet
(Gram Stain Reagent) Mordant
Gram’s Iodine
(Gram Stain Reagent) Decolorizer
Alcohol
(Gram Stain Reagent) Counterstain
Safranin
Gram result that has a thick peptidoglycan
Gram +
Gram result wherein the outer membranes have lipids, polysaccharide
Gram -
Gram result that has 90% peptidoglycan
Gram +
Gram result that has no teichoic acids
Gram -
Gram result that has teichoic acids
Gram +
Gram result that has a thin peptidoglycan
Gram -
Gram result that does not have many polysaccharies
Gram +
Color of Gram + test?
Purple/violet