SGL1 Quiz Flashcards
Wright’s stain is a stain that facilitates the differention of ____________
It is mixture of ______ and ____________ dyes.
It is primarily used to stain __________ and _____________.
Blood cell types
Eosin; Methylene blue
Peripheral blood smears; bone marrow aspirates
Toluidine blue has been used in identifying __________ and __________ of the oral cavity.
Use of toludine blue in tissue sections is done with the aim to highlight components, such as _____________,________, and ____________
Dysplasia; carcinoma
Mast cells granules, mucins; cartilage
Rotomy microtomes use what kind of knives?
Steel knives
In __________ immunocytochemistry, there is one antibody and one incubation. However in_________ immunocytochemistry, there are two antibodies and two incubations.
Direct; Indirect
Specimen thickness for Light Microscopes
10-40 microns
The toluidine blue stain is ________ and stains_________
Basic; RNA and DNA
Is a bright diffraction halo present in the Nomarski phase contrast microscope or in the phase contrast microscope?
Phase contrast microscope
What is the purpose of immunocytochemistry?
To visulaize the localization of a specific protein or antigen in cells by use of a specific primary antibody that binds to it.
What is the purpose of autoradiography?
To detect nucleic acid synthesis time
Why is fixation used?
To terminate cell metabolism
Prevent enzymatic degradation of cells and tissue by autolysis
Kill pathogenic microorganisms such as bacteria, fungi, and viruses
Harden tissue as a result of either crossling or denaturing protein molecules
What is the main benefit of confocal light microscope?
Light is focused at one point on tissue, which gives a better resolution and lets you see the layers
Common clearing solvents
Zylol
Toluol
Paraffin
Immunocytochemistry requires that cells under study are made___________, usually with a __________, so that antibody molecules can enter a cell and bind to the ____________
peermeable; detergent; antigen
Role of dehydration step
Remoe water and replace with alcohol
What replaces the alchol in the tissue?
Paraffin
What color do glycosaminoglycans stain? What is the phenomenon called?
Red; Metachromasia.
What is a benefit to using a phase contrast microscope?
Living cells can be examined without being killed, fixed, and stained.
Specimen thickness for Transmission Electron Microscopes
0.1 microns
Which florescent dyes can be used as marker?
Fluorescin (green fluorescence) or rhodamine (red fluorescence)
Nissl stain is a classic _________ staining method use on __________ sections.
Nucleic acid; nervous tissue
Periodic acid- Shiff (PAS) is a staining method used to detect______________
Polysaccharides
Maximum magnification for transmission electron microscopes
200,000x
Nissl staining typically marks the ______ due to ____________ as well as the nuclus and other accumulations of nucleic acid.
rER; rRNA
Light microscopes can be used to see what?
Organelles like nuclues, mitochondria, vaculoes, the golgi, and the nucleolus
Which microscope allows for the 3D reconstruction of an object?
Confocal light microscope
What are the four major staining properties exhibited the Wright’s stain?
Basophil- affinity for methylene blue
Azurophil- affinity for the oxidation products of methylene blue called azures)
Acidophil- Affinity for Eosin
Neutraphil- Affinity for a complex of dyes in the mixture
Most common stains used in light microscopes
H&E
3 steps in tissue processing
Fixation
Dehydration
Embedding
tool used to cut extremely thin slices of material, known as sections 2-50 microns
Microtomes
What are reasons to freeze tissue samples?
When you want rapid results
When you need to know if a tissue is cancerous
Which has a higher resoluton electron or light microscopes?
Electron
In what ways did Normarski phase contrast microscopy improve upon the phase contrast microscopy discovered in 1934?
It allows a greater depth of focus so one can visualize thicker specimens/ cells
Uses a special type of optical prism to produce a much improved pseudo 3D shadow image
PAS stains carbohydrate macromolecules mainly found where?
Connective tissues, mucus, the glycocalyx and basement membrane thickening.
Most common stains used with Transmission Electron Microscopy
uranyl acetate, lead citrate (heavy metal atoms reflect electrons in the beam)
Maximum magnification for light microscopes
2,000x
What type of particles are convenient markers for direct immunocytochemistry at the electron microscopic level?
Gold
Which type of immunocytochemistry is more specific?
Indirect
What are the steps of autoradiography?
- Deliver a radioactive precursor compund to the cells of tisse
- The tissue sections are prepared and covered with photograhic emulsion. The slides are kept in light-proof boxes
- After and adequate exposure time they are developed photographically and examined
- The silver bromide crystals present in the photographic emulsion are hit by radiation. They are transformed into small black granules of metallic silver, thus revealing the existence of radioactivity in the tissue.
Example of specimen that is viewed using a scanning electron microscope?
Nuclear pores
Which microscope is used to produce high- contrast images of transparent specimens?
Phase contrast microscope
What are two common components of Nissl stain?
Toluidine blue and cresyl violet
Characteristics of Formulin
Crosslined lysine residues
Does not alter 3D structure
Does not react well with lipids, so poor fixative of cell membranes
Toluidine blue has _____________ properties.
Metachromatic
In the PAS reaction, periodic acid forms __________ groups in sugars of ___________ by an __________ process.
Aldehyde; glycoproteins; oxidation
The most commonly used fixative is ___________
Formulin
What step of tissue processing permenantly preserves the tissue structure for subsequent treatment?
Fixation
What kind of knofe is used for ultramicrotome?
diamond knives
The cresyl Violet method uses basic ________ dye to stain ________ blue, and is used to highlight special features of ___________
aniline; RNA; neurons
Describe the Perl’s reaction for iron.
- Tissue sections are treated with hydrochloric acid to denature the binding proteins of the hemosiderin molecule, which is an iron storage complex, and thereby release ferric (3+) ions.
- Potassium ferrocyanide is then introduced. The ferric ions combine with this solution, resulting in the formation of ferric ferrocyanide, which is an insoluble bright blue pigment.
In which type of microscopy are heavy metals sprayed on the specimen to give a stronger image?
Scanning Electron Microscope
___________ are stains used in electon microscopes.
Heavy metals
Toluidine blue can stain sections that _________ stain cannot
Hemotoxylin and Eosin
Which diseases may be diagnosed the Perl’s reaction for iron?
Hereditary hemochromatosis and Hemosiderosis
