Histological Techniques Flashcards
Light Microscope
You can see some structure in the cell. Resolution is not as strong as TEM. Basement membrane is visible.
Resolution
Measure of ability to resolve specimen. Better resolution = more detail we can resolve
(wavelength of source) x 0.61 / numerical aperture
3 types of microscope
Light Microscope, Transmission Electron Microscope, Scanning Electron Microscope
Scanning Electron Microscope
Focus on surface topography
Transmission Electron Microscope
Best resolution microscope that can see inside organelle structures. Basal lamina is only visible at TEM level. Magnets focus a beam of electrons onto a slide
Hematoxylin and Eosin Stain (H&E)
Stains the nucleus and cytoplasm respectively
Periodic Acid Schiff (PAS stain)
Stains sugar residues (glycogen, glycoproteins)
Aldehyde Fuchsin
Stains elastic fibers and b-cells of the pancreatic islets.
Orecin stain
Stains collagen fibers and is a cytoplasmic counterstain
Silver stain
Stains the Golgi and reticular fibers
Osmium tetroxide
volatile and useful for staining membranes
Epon
substance that is used for harding of the structures
Fixation
Technique used to preserve tissue structure. Formalin (formaldehyde) is used to cross link proteins and other substances.
Freeze fracturing
Used for looking at the structure in the plasma membrane
P face
Protoplasmic face, internal face that makes contact with cytoplasm. Gives a look at the proteins that are imbedded in the lipid bilayers of the membranes.