After electrophoresis the separated DNA fragment can be vishualised ethidium bromide gel exposed UV light . These DNA fragments appear as _______ coloured bands :

Options

A. Orange
B. Blue
C. Silver
D. Green

Answer

**Step-by-Step Text Solution:**

1. **Understanding Electrophoresis**: Electrophoresis is a technique used to separate DNA fragments based on their size. The DNA fragments are negatively charged and move towards the positive electrode when an electric current is applied.

2. **Role of Ethidium Bromide**: Ethidium bromide is a fluorescent dye that intercalates between the bases of DNA. It is commonly used in gel electrophoresis to visualize DNA fragments.

3. **Exposure to UV Light**: After the electrophoresis process, the gel containing the separated DNA fragments is exposed to ultraviolet (UV) light. Ethidium bromide fluoresces under UV light.

4. **Visualization of DNA Fragments**: When the gel is exposed to UV light, the ethidium bromide bound to the DNA emits a fluorescent signal, allowing the DNA fragments to be visualized.

5. **Color of the Bands**: The DNA fragments appear as colored bands on the gel. Specifically, when exposed to UV light, these bands appear as orange-colored bands due to the fluorescence of ethidium bromide.

**Final Answer**: The DNA fragments appear as **orange** colored bands.

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