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Question
Which of the given statements is correct in the context of visualizing DNA molecules separated by agarose gel electrophoresis?
Options
DNA can be seen in visible light
DNA can be seen without staining in visible light
Ethidium bromide stained DNA can be seen in visible light
Ethidium bromide stained DNA can be seen under exposure to UV light
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Solution
Ethidium bromide stained DNA can be seen under exposure to UV light
Explanation:
DNA molecules separated by agarose gel electrophoresis are not visible in normal visible light and require staining. Ethidium bromide binds to DNA and fluoresces under UV light, allowing visualization of DNA bands as bright orange coloured bands. This method is widely used in laboratories for DNA analysis after gel electrophoresis.
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