Question

The separated DNA fragments can be visualised after staining with 'X' and exposure to 'Y'. The 'X' and 'Y' are

• A. \( \text{Ethidium iodide}, \, X = \text{X-Rays}, Y = \text{X-Rays} \)
• B. \( \text{Ethidium bromide}, \, X = \text{UV-Rays}, Y = \text{UV-Rays} \)
• C. \( \text{Ethidium chloride}, \, X = \gamma-\text{Rays}, Y = \gamma-\text{Rays} \)
• D. \( \text{Ethidium fluoride}, \, X = \beta-\text{Rays}, Y = \beta-\text{Rays} \)

Hint:

Ethidium bromide is widely used in molecular biology for DNA visualization after electrophoresis. It binds to DNA and fluoresces under UV light.

Answer 1

The Correct Option is B

Step 1: The correct combination of staining agent and radiation exposure for visualising DNA fragments is Ethidium bromide, which binds to DNA and is commonly used with UV light exposure.
Step 2: X refers to the staining agent, and Y refers to the type of radiation used for visualisation. UV light is effective for detecting the bound Ethidium bromide on the DNA.