electron microscopy

electron microscopy,

a technique using an electron microscope in which a beam of electrons is focused by an electromagnetic lens and directed onto an extremely thin specimen. The electrons emerging are focused and directed by a second lens onto a fluorescent screen. The magnified image produced is 1000 times greater than that produced by an optic microscope and well resolved, but it is two-dimensional because of the thinness of the specimen. Also called transmission electron microscopy. Compare scanning electron microscopy, transmission scanning electron microscopy.

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electron

any of the negatively charged particles arranged in orbits around the nucleus of an atom and determining all of the atom's physical and chemical properties except mass and radioactivity. Electrons flowing in a conductor constitute an electric current; when ejected from a radioactive substance, they constitute the beta particles.

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electron acceptor

see oxidant.

electron beam

the stream of electrons that flows from the anode to the cathode in the x-ray tube and then interacts with the tungsten target to produce x-rays.

electron carrier

a molecule associated with membrane-bound proteins that accepts and transfers electrons.

electron donor

see reductant.

electron micrographs

photographic images of electron microscopic fields.

electron microscope

see electron microscope.

electron microscopy

technology of using an electron microscope.