Laboratory Bio-Techniques · Zoology

Which substance is commonly used to visualize DNA bands in a gel?

  1. Coomassie blue dye
  2. Ethidium bromide
  3. Safranin O stain
  4. Crystal violet dye
Show answer and explanation

Correct answer: Ethidium bromide

Ethidium bromide intercalates between DNA base pairs and fluoresces orange under UV light, making DNA bands visible after gel electrophoresis. It is one of the most widely used DNA stains, though safer alternatives such as SYBR Safe are now also common.

Difficulty: Medium Question 8 of 20

Practice all 20 Laboratory Bio-Techniques questions

Keep practicing

More Laboratory Bio-Techniques questions