"The Living Cell"

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…instruments use special equipment to reveal the refraction, or bending, of light passing through objects, enabling the viewer to see cell details not visible with other microscopes. The electron microscope uses waves of electrons, rather than light, and magnetic fields, rather than lenses, to get an image. With the aid of electron microscopes 200 times more powerful than the best light instruments, molecular biologists have learned a great deal more about the tiny structures within cells.