Microscopy & Staining – Flashcards
Unlock all answers in this set
Unlock answersMicroscopy: The instrument  |
A simple microscope has only one lens |
Light Microscopy |
The use of any kind of microscope that uses visible light to observe specimens. |
Compound Light Microscope  |
In a Compound Light Microscopy the image from the objective lens is magnified again by ocular lens. |
Total Magnification = |
Objective lens X Ocular lens |
Compound Light Microscopy (Resolution) |
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Compound Light Microscope (Refractive Index) |
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Brightfield Illumination |
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Darkfield Illuminaton  |
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Phase-Contrast Microscopy |
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Diffential Interference Contrast Microscopy DIC |
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Fluorescence Microscopy |
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Confocal Microscopy |
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Two-Photon Microscopy  |
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Scanning Acoustic Microscopy SAM |
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Atomic Force Microscopy |
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Electron Microscopy  |
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Transmission Electron Microscopy TEM |
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Scanning Electron Microscopy SEM |
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Sanned-Probe Microscopy STM |
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Atomic Force Microscopy AFM Â |
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Preparation of Specimens for Light Microscopy |
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Staining: Â |
Coloring the microbe w/ dye that emphasizes certain structures. done to increase contrast. |
Smear: |
A thin film of a solution of microbes on a slide. A smear is usually fixed to attached the microbes to slide and to kill the microbes. |
Stains consist of: |
a Positive and Negative Ion |
Basic Dye |
The Chromophore is a Cation |
Acid Dye |
The chromophore is an anion |
Negative Staining |
Staining the background instead of the cell |
Some basic dyes used in class are: |
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Simple Stain |
use of a single basic dye |
A mordant |
may be used to hold the stain or coat the specimen to enlarge it. |
Differential Stains |
* gram stain and acid-fast stain
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Gram Stain |
Classifies bacteria into gram-positive or gram-negative |
Gram positive bacteria |
tend to be killed by penicillin and detergents |
Gram Negative Bacteria |
Bacteria is more resistant to antibiotics |
Whats the color of Gram-Positive cells when stained with Crystal violet,mordant (iodine),decolorizing agent (alcohol-acetone), and counterstain (Safranin)? Â |
All 4 result in Purple |
Whats the color of Gram-Negative cells when stained with Crystal violet,mordant (iodine),decolorizing agent (alcohol-acetone), and counterstain (Safranin)? Â |
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Acid-Fast Stain |
One that differentiates bacteria into distinctive groups binds strongly only to bacteria that have waxy material in the cell wall is not decolorized by acid-alcohol Ex:
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Special Stains |
used to distinguish parts of cells in microrganisms. Capsule Stain Endospore Stain Flagella Stain  |
Negative Staining for Capsules |
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Endospore Staining |
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Flagella Stain |
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Types of Stains |
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