_____ is a store house of collected plant specimens that are dried, pressed ad preserved on sheets.

Answer

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

1. **Understanding the Question**: The question asks for a term that describes a storehouse for collected plant specimens that are dried, pressed, and preserved on sheets.

2. **Identifying the Term**: The term that fits this description is "herbarium." A herbarium is a collection of preserved plant specimens that are used for scientific study.

3. **Characteristics of a Herbarium**:
- **Preservation Method**: In a herbarium, plant specimens are dried and pressed onto sheets. This process helps in preserving the physical characteristics of the plants for future reference.
- **Types of Specimens**: Both whole plants and parts of plants (like leaves, flowers, and stems) can be preserved in a herbarium.
- **Additional Information**: Each specimen is typically accompanied by labels that provide important information such as the location where the plant was collected, the date of collection, and details about the plant's habitat and morphological features.

4. **Importance of Herbarium**: Herbariums are essential for taxonomical studies and help scientists understand the similarities and differences between various plant groups.

5. **Conclusion**: Therefore, the answer to the question is "herbarium."

**Final Answer**: Herbarium

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