Biotechnology Principles And Processes Question 5
Question: Upon exposure to UV radiation, DNA stained with ethidium bromide will show
(1) Bright red colour
(2) Bright blue colour
(3) Bright yellow colour
(4) Bright orange colour
Show Answer
Answer: (4) Bright orange colour
Explaination-
Ethidium bromide provide bright orange colour to DNA. Ethidium bromide (EtBr) or 3,8-Diamino-5-ethyl-6-phenylphenanthridinium is commonly used as a non-radioactive marker to stain DNA in order to identify and visualize nucleic acid bands in electrophoresis and other gel-based methods of nucleic acid separation.
The mode of binding of EtBr is intercalation between the base pairs. This binding changes the charge, weight, conformation, and flexibility of the DNA molecule.
