ELECTRON MICROSCOPY Objects smaller than 0 . 2 μ m cannot be clearly viewed with a light microscope. They require the use of an electron microscope. Viruses and tiny internal cell structures would be examples. These microscopes use a beam of electrons, with its much shorter wavlength, for illumination instead of light rays, so the resolution is much greater (2.5 nm compared to 0.2 μ m for light microscopes). Images produced appear on a screen and are photographed. Types of electron microscopes: • Transmission Electron Microscopy (TEM)--- the beam of electrons is passed through a very thin-sliced specimen. Electromagnets are used to focus. Objects are most often magnified 10,000- 100,000X or even more. Since the beam of electrons has much less penetrating power than light rays, the specimen must be sliced very
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This note was uploaded on 01/23/2012 for the course MCB MCB2010 taught by Professor Smith during the Fall '09 term at Broward College.