Staining and Culture Media Flashcards
A procedure that is meant to give color to the organisms, making them easier to see under the microscope
Staining
A type of staining that makes use of a single dye which can either be aqueous (water-based) or alcohol-based
Simple staining
This method of staining is a quick and easy way to visualize cell shape, size, and arrangement of bacteria
Simple staining
A type of staining that uses safranin, methylene blue, or crystal violet
Simple staining
Application of heat to a bacterial smear preparation. This procedure simultaneously kills and attaches the bacteria to the slide
Heat fixation
What are types of staining?
Simple staining
Differential staining
Special staining
A type of staining that are used to differentiate one group of bacteria from another
Differential staining
What are the two types of differential staining?
(1) Gram stain
(2) Acid fast stain
A type of differential staining that distinguishes gram-positive bacteria from gram-negative bacteria
Gram stain
What color will gram-positive bacterias if stained?
blue/purple
What color will gram-negative bacterias if stained?
red/pink
As general rule, all cocci are gram-positive except what?
Neisseria
Veilonella
Branbamella
As general rule, all bacilli are gram-negative except what?
Corynebacterium
Clostridium
Bacillus
Mycobacterium
A type of differential staining that is used for bacteria with high lipid content in their cell wall, hence cannot be stained using Gram stain
Acid-fast stain
What are the two methods in staining acid-fast bacteria?
Ziebl-Neelsen stain (hot method)
Kinyoun stain (cold method)
A stain known as “hot method” because it requires steam - bathing the prepared smear after addition of the primary dye
Ziebl-Neelsen stain
In using Ziebl-Neelsen stain, acid-fast organims will appear in what color?
red on a blue background
In using Kinyoun stain, acid-fast organims will appear in what color?
red on a green background
A stain known as “cold method” as it does not utilize heat after addition of the primary stain, which is oil-based
Kinyoun stain
A type of stain that are used to demonstrate specific structures in a bacterial cell
Special stain
Metachromatic granules can be visualized using what stain?
Loeffler Alkaline Methylene Blue (LAMB) stain
Stain used to visualize capsule or slime layer
Hiss stain
Stain used to visualize cell wall
Dyer stain
Stain used to visualize flagella
Fischer-Conn stain
Stain used to visualize spores
Dorner and Schaeffer-Fulton stain
Stain used to visualize capsule of the fungus Cryptococcus neoformans
India ink or nigrosine
Are used to grow microorganisms
Media
An aqueous solution to which all the necessary nutrients essential for the growth of microorganisms are added
Culture medium
What are the three primary levels of classification of culture media?
(1) Physical state
(2) Chemical composition
(3) Functional type
Commonly called broths, milk, or infusions; these are water-based solutions that do not soldify at temperatures above freezing point
Liquid media
Media that contain specific amounts of nutrients but do not contain gelling agents such as gelatine or agar
Liquid media
Media that are suited for the propagation of a large number of organisms, fermentation studies, and other tests
Liquid media
A media that exhibit a clot-like consistency at ordinary room temperature and contain agar at concentrations of 0.5% or less that allows thickening of the media without producing a firm substance
Semi-solid media
A media that have a consistency similar to custard and are best suited for culture of microaerophilic bacteria or for the study of bacterial motility
Semi-solid media
A media that contain a solidifying agent such as 1.5%-2% agar, giving them a firm surface on which cells can form discrete colonies
Solid media
A media used for isolation of bacteria and fungi or for determining the colony characteristics of the organisms under study
Solid media
Two forms of solid media
(1) liquefiable (or reversible) solid media
(2) non-liquefiable (or irriversible) solid media
A media that contain chemically defined substances which are pure organic and/or inorganic. Their precise chemical composition are known which may be simple, complex, depending on what supplement is added to it
Synthetic media
A type of media that is complex and contain at least one ingredient that is not chemically defined, which means that neither a simple or pure compound
Non-synthetic media
A media that is not representable by an exact chemical formula. Most are extracts of animals, plants, or yeasts
Non-synthetic media
A media that can support the growth of more fastidous organisms
Non-synthetic media
A media that is designed for primary isolation of a broad spectrum of microbes and contain a mixture of nutrients that support the growth of both pathogenic an non-pathogenic organisms
General purpose media
A media that contain complex organic substances such as blood, serum, or special growth factors, and are designed to increase the number of desired microorganisms without stimulating the rest of the bacterial population
Enrichment media
A media used to grow fastidious or nutritionally exacting bacteria
Enrichment media
What are the two commonly used enrichment media?
(1) Blood agar
(2) Chocolate agar
A type of nutrient medium that contains general nutrients with 56-100% (by volume) blood added to a blood agar base
Blood agar
Certain gram-positive bacteria produce exotoxins that causes ____ of red blood cells contained in the blood agar
Hemolysis (destruction of red blood cells)
A type of nutrient medium that is used for the culture of fastidious organisms such as Haemophilus sp. where heat is applied to lyse the red blood cells, causing the medium to turn brown
Chocolate agar
A media that contain one or more substances that encourage the growth of only a specific target microorganism and inhibit the growth of others
Selective media
A media that is designed to prevent the growth of unwanted contaminating bacteria or commensals so only the targeted bacteria will grow
Selective media
A media that is usually agar-based solid media that allow isolation of individual bacterial colonies
Selective media
A type of culture medium that contains the antibiotics trimethroprim, nystatin, vancomycin, and colistin. It is used for the isolation of Neisseria
Thayer-Martin agar
A type of culture medium that contains 10% NaCl and used for the isolation of Staphylococcus areus
Mannitol Salt agar
A type of culture medium that promotes the growth of gram-negative bacteria, primarily those belonging to the family Enterobacteriaceae, and inhibits the growth of gram-positive bacteria. It is both selective and differential
MacConkey’s agar
Using MacConkey’s agar, in order to inhibit the growth of gram-positive bacteria, they used what?
Bile salt
A type of selective medium that is used to recover Mycobacterium tuberculosis. It is made selective by the incorporation of malachite green
Löwenstein-Jensen medium
A culture medium used for the isolation if fungi
Saboraud’s dextrose agar
A type of media that allows the growth of several types of microorganisms. These are designed to show visible differences among certain groups of microorganisms
Differential media
A media that allow the growth of more than one target microorganisms that demonstrate morphologic varations in colony morphology
Differential media
A media used for clinical specimens that need to be transported to the laboratory immediately after collection
Transport media
This media prevent the drying of specimen and inhibit the overgrowth of commensals and contaminating organisms
Transport media
This is added in transport media specimens to neutralize inhibitory factors
Charcoal
A media used specifically for organisms that cannot survive in the presence of oxygen and require reduced oxidation-reduction potential and other nutrients
Anaerobic media
This media is supplemented with nutrients such as vitamin K and hemin
Anaerobic media
This media used methylene blue or reazurin as an indicator of the oxidation-reduction potential
Anaerobic media
