Name the instruments which are used to study structures that cannot be seen with naked eye.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for instruments that help us study structures that are too small to be seen with the naked eye. This implies that we need tools that can magnify these small structures.

2. **Identifying the Instrument**: The primary instrument used for this purpose is the microscope. Microscopes are specifically designed to magnify small objects, making them visible for study.

3. **Types of Microscopes**: There are different types of microscopes, including:
- **Light Microscope**: Uses visible light and lenses to magnify objects.
- **Electron Microscope**: Uses a beam of electrons for much higher magnification and resolution than light microscopes.

4. **Applications of Microscopes**: Microscopes are used to study various small structures, such as:
- Cells: The basic unit of life.
- Organelles: Specialized structures within cells, like mitochondria and chloroplasts.

5. **Conclusion**: Therefore, the instrument used to study structures that cannot be seen with the naked eye is the microscope.

**Final Answer**: The instrument used to study structures that cannot be seen with the naked eye is the microscope.

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