a CHUNG WEM YING 7 éve
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Microscopy
Microscopy involves the use of various types of microscopes, such as light and electron microscopes, to observe microorganisms and cells that are otherwise invisible to the naked eye.
Megnyitás
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
