Question

how does a DNA viewed in a agarose gel?
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Answer 1

DNA as well as RNA are normally visualized by staining with ethidium bromide, which intercalates into the major grooves of the DNA and fluoresces under UV light. ... The ethidium bromide may be added to the agarose solution before it gels, or the DNA gel may be stained later after electrophoresis.

Answer 2

The proteins may be separated by charge and/or size (isoelectric focusing agarose electrophoresis is essentially size independent), and the DNA and RNA fragments by length. ... The separated DNA may be viewed with stain, most commonly under UV light, and the DNA fragments can be extracted from the gel with relative ease.

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