CHAPTER 1 Pt. 2 Histology and Its Methods of Study Flashcards
Cell surface glycoproteins and mucin are
PAS-positive because of their high content of ___________
and _________
oligosaccharides; polysaccharides
LESS common method of staining
Metal Impregnation
Metal Impregnation uses ______ or ______ to have visual certain ECM fibers and specific cellular components in nervous tissue such as dendrites or dendritic spines
silver; gold
Metal Impregnation for Cerebral Cortex exposes what component?
cytoplasmic process
We avoid these dyes for metabolic diseases diagnosis that intracellular accumulations of cholesterol, phospholipids, or glycolipids
Lipin Soluble Dyes such as Sudab black
it is a modification of PAS procedure; stains DNA of cell nuclei
Feulgen Reaction
Slide preparation, from tissue fixation to observation
with a ______________, may take from 12 hours to 2½ days,
depending on the size of the tissue, the embedding medium,
and the method of staining.
light microscope
The final step before microscopic
observation is mounting a __________________________ on the
slide with clear adhesive.
protective glass coverslip
The optical
components of a bright-field microscope
condenser
objective
eyepiece
focusing light on the object
to be studied
condenser
lens enlarging and projecting the
image of the object toward the observe
objective
further magnifying this image and projecting
it onto the viewer’s retina or a charge-coupled device
eyepiece/ocular lens
The total magnification is obtained by multiplying the_______________ and ____________
magnifying power of the objective and ocular lenses.
The critical factor in obtaining a crisp, detailed image
with a light microscope is its
resolving power
defined as the
smallest distance between two structures at which they can be
seen as separate objects.
resolving power
The maximal resolving power of the
light microscope is approximately
0.2 μm
maximal resolving power can permit
clear images magnified __________ times
1000-1500
Objects smaller or
thinner than 0.2 μm cannot be distinguished with this instrument.
light microscope
typically used for study of bright-field microscopic preparations, involves the conversion of a stained tissue preparation to high-resolution digital images
and permits study of tissues using a computer or other digital device, without an actual stained slide or a microscope.
Virtual microscopy
When certain cellular substances are irradiated by light of a
proper wavelength, they emit light with a longer wavelength—
a phenomenon called
fluorescence
tissue sections are usually irradiated with ultraviolet (UV) light and the emission is in the visible portion of
the spectrum.
fluorescence
microscopy
Acridine orange binds nucleic acids and causes DNA in cell
nuclei to emit _________ light and the RNA-rich cytoplasm to
appear ______ in these cells of a kidney tubule.
yellow; orange
DAPI
(4′,6-diamino-2-phenylindole)
Cultured cells stained with DAPI (4′,6-diamino-2-phenylindole)
that binds DNA and with fluorescein phalloidin that binds actin
filaments show nuclei with ____ fluorescence and actin filaments
stained _____.
blue; green
Living neural crest cells growing in culture
________: Without fixation and staining, only
the 2 pigment cells can be seen.
Bright-field microscopy
Cell boundaries, nuclei, and
cytoplasmic structures with different refractive indices affect
in-phase light differently and produce an image of these features
in all the cells
Phase-contrast microscopy
Cellular details
are highlighted in a different manner using Nomarski optics.
Phase-contrast microscopy, with or without differential interference, is widely used to observe live cells grown in tissue culture
Differential interference contrast microscopy
in a bright field microscope, excess light reduces contrast within the image and compromises the resolving power of the objective lens, what specific type of microscopy avoids these problems?
Confocal microscopy
Confocal microscopy achieves high resolution and sharp focus by using
(1) a small point of _____________, often from a laser and
(2) a plate with a
_________ aperture in front of the image detector.
high-intensity light; pinhole
allows the recognition of stained or
unstained structures made of highly organized subunits
Polarizing microscopy
The ability to rotate the direction
of vibration of polarized light is called
birefringence
DIFFERENT MICROSCOPIES UNDER LIGHT MICROSCOPY?
Bright-field
Fluorescence
Phase-Contrast
Confocal
Polarizing
this type of microscopy has longer wavelength, less distinction
Light Microscopy
it has black background; white/clear vision of the tissue components; used to detect ________
Dark-field Microscopy; syphilis
scan tissues at different level; reconstruct 3d image
confocal
like an x-ray; 2d
transmission electron microscopy
x-ray but 3d
scanning electron microscopy
In polarizing Microscopy, there is an intense color of yellow, or orange birefringence. What component of the sample are these colors?
collagen fibers for unsectioned mesentery
The wavelength in an electron beam is much shorter than that
of light, allowing a 1000-fold increase in resolution.
ELECTRON MICROSCOPY
an imaging system that permits resolution around 3 nm
Transmission Electron Microscopy
Very thin (__-___ nm),
resin-embedded tissue sections are typically studied by TEM
at magnifications up to approximately 120,000 times
40-90
There are shades of gray region, black and white image.
TEM (Transmission Electron Microscopy)
in TEM, if an electron passed readily it means?
electron lucent (brighter)
in TEM, if electrons were absorbed or deflected
electron dense
