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Questions About Cancer? 1-800-4-CANCER

NCI Dictionary of Cancer Terms

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ion  listen  (I-on)

  An atom or a molecule that has a positive or negative electrical charge. Examples are sodium, potassium, calcium, chloride, and phosphate. These ions help move nutrients into cells, help move waste out of cells, and help nerves, muscles, the heart, and the brain work the way they should.