Final answer:
Transmission electron microscopes offer high levels of magnification above 100,000 times and use an electron beam as the radiation source. Magnification is adjusted through changes in current to magnetic lenses.
Step-by-step explanation:
The characteristics of a transmission electron microscope include the highest practical magnification over 100,000 times, the use of an electron beam for the radiation source, and changing the magnification by adjusting the current to the magnetic lenses. Unlike optical microscopes, electron microscopes do not use visible light or glass lenses. Rather, they use electromagnetic lenses to focus the electron beam. The magnification in a transmission electron microscope can be changed by adjusting the current passing through these electromagnets, creating stronger or weaker magnification.
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