They can only gather refracted electrons over a very

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they can only gather refracted electrons over a very small angle, but the decrease in wavelength more than compensates. Resolution of TEM is 0.2-0.3 nm, 1000x better than light microscopes.
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Yves Brun Whole-mounted bacteria viewed by TEM
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Bacillus subtilis Containing endospore Scale bar = 100 nm Thin sections of bacteria allow us to see interior details Samples are frozen or embedded in a hard resin, then cut into sections 20-60 nm thick. Chemical treatments are used to create contrast. Stains such as OsO 4 have high atomic mass and scatter electrons to produce a dark image on a light background.
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Fluorescence microscopy Fluors are molecules that absorb light at one wavelength (shorter) and emit light at another wavelength (longer). In immunofluorescence microscopy , an antibody that recognizes a specific protein is covalently attached to a fluor. Fixed cells are treated with the antibody and observed under a microscope. Light of a specific wavelength is hits the sample to excite the fluor, and longer-wavelength photons emitted by the fluor are observed. fluorescein isothiocyanate
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Green Fluorescent Protein (GFP) Isolated from jellyfish Aequoria victoria Three amino acids of the protein cyclize inside the barrel to form a fluor that absorbs blue light and emits green light. Protein X GFP Unlike chemical fluors, GFP is a protein with a corresponding gene. Using recombinant DNA technology, we can connect the gene for a protein of interest to the gene for GFP, express this fusion protein in living bacteria , and observe its location using fluorescence microscopy.
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Excite with blue light GFP attached to Protein X emits green light GFP imaging GFP fused to a Caulobacter protein CtrA
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