HISTOTECHNOLOGY TEST 2 YEAR 3 verified to pass

HISTOTECHNOLOGY TEST 2 YEAR 3 What stains are used for the detection of acid fast bacteria? - correct answers Kinyoun, Ziel-Neelson, Fite, Auramine-rhodamine fluorescence List the types of pathogenic microorganisms - correct answers Bacteria, Fungi, Viruses, Protozoans, Prions Which microorganism requires extended time in formic acid to be inactivated? - correct answers prions What clues may be present on an H and E to indicate the need for microorganism staining? - correct answers increased lymphocytes or neutrophils, tissue necrosis, cellular changes What are the systems we use to classify bacteria? - correct answers Gram stain, shape, and acid fast What is the purpose of the gram stain - correct answers Differentiates between organisms with thick peptidoglycan layers (Gram pos) and gram negative organisms. List the steps of the reagents of the gram stain method for histological samples. - correct answers Crystal violet --> Gram's Iodine --> Decolorization agent (acetone/acids/alcohol) --> Basic fuchsin --> decolorization agent --> picric acid (neutral red/fast green in Thwart's method) Which cells take up the crystal violet? - correct answers Both gram positive and gram negative What are the components of gram's iodine? - correct answers iodine, potassium iodide, water What does the decolorizing agent do in the gram stain? - correct answers disrupts the thin cel walls of gram negative bacteria to remove the crystal violet/iodine complex What is the counterstain in the gram stain? - correct answers basic fuchsin What does picric acid, or neutral red/ fast green stain in the gram stain? - correct answers Remaining tissue elements that are not bacteria Which type of bacteria are best detected using acid fast methods? - correct answers Mycobacteria What are mycobacteria? - correct answers Rods that exhibit fungus-like, filamentous growth Why do mycobacteria not stain well with the gram stain? - correct answers Mycolic acid in their capsules make them resistant What is the general principle of acid fast staining? - correct answers Acid fast positive organisms have a high proportion of lipids in their cell capsules which make them resistant to decolorization by dilute mineral acids. What is the primary stain for the Kinyoun method? - correct answers carbol-fuchsin What is the decolorizing agent for Kinyoun method? - correct answers dilute mineral acid Why can't Kinyoun be used to detect M. leprae - correct answers It has a more fragile lipid capsule Which fixatives should be avoided with Kinyoun methods? - correct answers Alcoholic based fixatives can dissolve the mycolic acids (Carnoy's, Gendre, Zinc formalin) True or false: Carbol-fuchsin is more soluble in lipids - correct answers True How is cross contamination avoided when performing acid fast techniques? - correct answers A second control tissue with uterus is run alongside the acid fast tissue and used with the same waterbath, microtome, etc. and it should be negative for AFB.