Question

Which of the given statement is correct in the context of observing DNA
separated by agarose gel electrophoresis?
a. DNA can be seen in visible light
b. DNA can be seen without staining in visible light
c. Ethidium bromide stained DNA can be seen in visible light
d. Ethidium bromide stained DNA can be seen under exposure to
UV light



NCERT Class XII
Biology - Main Course Book

Chapter 11. Biotechnology: Princeples and Processes

Answer 1

d. Ethidium bromide stained DNA can be seen under exposure to
UV light     is the correct answer.

Answer 2

“Ethidium bromide stained DNA” can be seen under exposure to UV  is the correct statement in context of observing “DNA separated by agarose gel”.

Answer: Option d

Explanation:

• The ethidium bromide is added in the buffer to separate the DNA by the agarose gel electrophoresis process.
• This is used because the DNA binds with the molecule and the binding pattern can be seen.
• By the addition of the ethidium bromide in the gel it will be very easy to determine and visualizing the DNA pattern and the result of the electrophoresis.