によって CHUNG WEM YING 8年前.
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Microscopy
Microscopy
compound microscope
total magnification=objective lens magnificationxocular lens magnification
ocular lenses magnification(10x)
objective lenses magnification (10x,40x and 100x/oil-immension lens.)
illuminator,condenser,objective lenses,ocular lenses
uses visible light as a source of illumination
image formed by action of more than 2 lenses
resolution
the ability to distinguish two adjacent points
magnification
size of the image or point
types of light microscopes
confocal microscopy
transmission electron microscope
scanning electron microscope
fluorescence microscope
has application in medical microbiology and microbial ecology studies
shows a bright image of the object resulting from the fluorescent light emitted by the specimen
specimens usually staubed with fluorochromes
exposes specimen to UV ,violet or blue light
resolving power 100 times than light microscopes
the wavelength of electron microscope is only 0.01 Ǻ
employs a beam of electron in place of light wave to produce the magnified image
phase contrast microscope
some light rays from hollow cone of light passing through unstained cell slowed/out of phase(dark against bright background)
excellent way to observe living cells
stain is not necessary,view internal structures of living organisms
converts differences in refractive index/cell density into detected variations in light intensity
dark-field microscope
image is formed by light reflected or refracted by specimen
used to identify bacteria such as Trepanoma pallidum,the causative agent of syphilis
used to observe internal structures in eukaryotic organism
used to observe living,unstained preparations
produce a bright image of the object against a dark background
bright-field microscope
produce dark image against a brighter background
Units of measurement
microbes and structural components->micrometers,nanometers,angstroms
metric system
preparation of specimens for light microscopy
wet mount
smears
staining
special staining
differential staining
simple staining
fixation
preparing smear
electron microscope
mycoplasma,viruses,ribosomes,proteins,lipids,small molecules,atoms
light microscope
magnification due to objective lens or ocular lens
properties of light
absorption,transmission,reflection,refraction
eukaryotic cells,nucleus,most bacteria,mitochondrion
types of stain
iodine,methylene blue,eosin Y,Toluidene blue,Wright's stain,crystal violet,aceto-orcein,Sudan III
goals of microscopy
render the details visible to the human eye or camera
separate the details in the image
produced a magnified image of the specimen
introduction to microscope and microscopy
microscope->instrument to observe microorganism
light microscope,electron microscope
cells are microscopic
