Question

Arrange the given steps involved in gel electrophoresis used for separation of DNA fragments?
(A) Exposure to UV light
(B) Staining with ethidium bromide
(C) Moving of DNA fragments towards anode
(D) Elution

• A. (A), (B), (C), (D)
• B. (B), (A), (D), (C)
• C. (A), (D), (B), (C)
• D. (C), (B), (A), (D)

Hint:

Remember that the movement of DNA is towards the anode because DNA molecules are negatively charged.

Answer 1

The Correct Option is B

To separate DNA fragments through gel electrophoresis, the steps must follow a logical order for effective separation:
Step 1: Staining with ethidium bromide
First, the DNA fragments are stained with ethidium bromide. This chemical binds to the DNA and allows it to be visualized under UV light.
Step 2: Exposure to UV light
After staining, the gel containing the DNA is exposed to UV light. This exposure makes the DNA, which is bound to ethidium bromide, fluoresce and become visible for further analysis.
Step 3: Elution
The DNA fragments are then eluted from the gel. Elution involves separating the DNA from the agarose gel for further use or analysis.
Step 4: Moving of DNA fragments towards the anode
As the electric field is applied, the DNA fragments, being negatively charged, start moving towards the anode. This movement allows the separation of DNA based on size, with smaller fragments traveling faster through the gel.
\boxed{\text{Correct Order: (B), (A), (D), (C)}}