Fluidity of bio-membranes can be shown by

Options

A. Tissue culture
B. Fluorescence microscope
C. Phase-contrast microscope
D. Electron microscope

Answer

To answer the question "Fluidity of bio-membranes can be shown by," we will evaluate each of the provided options step by step.

### Step-by-Step Solution:

1. **Understanding Fluidity of Biomembranes**:
- Biomembranes, particularly the plasma membrane, exhibit fluidity which is essential for various cellular functions such as transport, communication, and mobility of proteins and lipids within the membrane.

2. **Evaluating Option 1: Tissue Culture**:
- Tissue culture refers to the growth of tissues or cells in an artificial medium. It does not provide any direct information about the fluidity of biomembranes.
- **Conclusion**: This option is **incorrect**.

3. **Evaluating Option 2: Fluorescence Microscope**:
- A fluorescence microscope uses fluorescent stains to visualize structures within cells. When cells are stained, they emit light when exposed to UV light, allowing observation of the distribution and movement of membrane components.
- This technique is particularly useful for demonstrating the fluidity of biomembranes as it can show how proteins and lipids move within the membrane.
- **Conclusion**: This option is **correct**.

4. **Evaluating Option 3: Phase Contrast Microscope**:
- A phase contrast microscope enhances the contrast in transparent specimens, allowing for visualization of cells and their components. However, it does not provide information about the fluidity of biomembranes.
- **Conclusion**: This option is **incorrect**.

5. **Evaluating Option 4: Electron Microscope**:
- An electron microscope provides high-resolution images of cellular structures but does not allow for the observation of dynamic processes such as membrane fluidity.
- **Conclusion**: This option is **incorrect**.

### Final Answer:
The fluidity of bio-membranes can be shown by the **fluorescence microscope**.

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