Demonstration of Bacteria Flashcards
Composition of stains?
- Negative ion
- Positive ion
It combines with the cellular elements that are acidic in nature?
Cationic/Basic
Examples of Cationic/Basic dyes?
Crystal violet, Methylene blue, Malachite green and Safranin
It combine with the cytoplasmic components of the cells that are alkaline in nature.
Acid fuchsin, Eosin, Nigrosine
Use of ONE DYE for ALL cells are stained with the SAME COLOR
Simple stains
It distinguish TWO kinds of microorganisms
Differential Stains
Example of Simple Stains
Methylene blue, Crystal violet, Safranin, Carbol fuchsin
Example of DIFFERENTIAL STAINS?
Gram stain and Acid-fast stain
It highlights specific cell structures
Special Stains
It is commonly used stain that helps us see microscopic life in brilliant color.
Methylene blue staining
It shows the characteristic morphology of polymorphs, lymphocytes and other cells more clearly.
Methylene blue staining
First devise by histologist Hans Christian Gram in 1884 as a method of staining bacteria in tissues.
Gram Staining
Primary Stain in Gram Staining?
Crystal Violet
Mordant in Gram Staining?
Lugol’s Iodine
Decolorizer in Gram-Staining?
Acetone-Alcohol
Counterstain in Gram-Staining?
Safranin
Applications of Gram Stain
- It is important therapeutically
- Sometimes diagnostic
It was first introduced by Paul Ehrlich in 1882.
Acid-fast staining
Primary stain of acid-fast staining?
Carbol fuchsin
Mordant of acid-fast staining?
Heat
Decolorizer of acid-fast staining?
Acid-alcohol
Counterstain of acid-fast staining?
Methylene blue
It enables the acid-fast bacteria to retain the color of the primary stain (carbol fuchsin) because they contain?
Mycolic acid
A waxy substance that does not allow the decolorizer to enter into the cell wall due to its waxy nature.
Mycolic acid
Preparing colorless bacteria against a colored background?
Negative stain
Negative stain is a type of capsule staining that is a?
Special stain
- The endospore are stained with malachite green; heat is used to provide stain penetration.
- The rest of the cell is then decolorized, and counter stained a light red safranin.
Endospore Staining
Rendered visible if they are thickened by impregnation of silver on the surface, so that they become visible under ordinary microscope.
Special Stain: Impregnation Methods
Uses of microscope?
- Initial detection of microbes
- Preliminary or definitive identification of microbes
It refers to the use of any kind of microscope that uses VISIBLE LIGHT to observe specimens.
Light microscopy
The most common type of light microscope, and the easiest to use and evenly illuminates the field of view?
Bright-field microscopy
- It uses a dark-field condenser that contain an opaque disk.
Dark-field microscopy
In this microscope, 1 set of light rays comes directly from the light source. While, the other set comes from light that is reflected or diffracted from a particular structure in the specimen.
Phase-contrast microscopy
It takes advantage of the ability of substance to absorb short wavelengths of light and give off light at a longer wavelength.
Fluorescent microscopy
A diagnostic techniques; employs for detection of antigen (direct fluorescent antibody technique)
Fluorescent antibody technique
Diagnostic technique; employed for detection of antibodies
Indirect fluorescent antibody methods
Lenses focus a laser beam to illuminate a givent point on one vertical plane of a specimen.
Confocal microscopy
- To obtain 3D images
- To evaluate cellular physiology
Uses of Confocal Microscopy
- It used electromagnetic lenses, electrons, and a fluorescent screen to produce the magnified image.
Electron microscopy
- Electrons pass through the specimen and are scattered.
- Magnetic lenses focus the image onto a fluorescent screen or photographic plate.
Transmission electron microscopy
- Primary electrons sweep across the specimen and knock electrons from its surface.
- These secondary electrons are picked up by a collector, amplified, and transmitted onto a viewing screen or photographic plate.
Scanning electron microscopy
- It map the bumps and valleys of a surface on an atomic scale.
- Their resolving power is much greater than the electron microscope, and the samples do not need special preparation as they do for electron microscopy.
Scanning-probe microcopy
They are used to provide incredibly detailed views of molecules such as DNA.
Scanning tunneling microscopy
They produce 3D images of the surface of a molecule.
Atomic force microscopy
