Which cell structure stores water, sap, exretory product and other materials not useful for the cell?

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks for the cell structure that stores water, sap, excretory products, and other materials that are not useful for the cell.

2. **Understand the Function of Storage**: We need to find a cellular organelle that is primarily responsible for storage within the cell.

3. **Recall Relevant Cell Structures**: Consider various cell organelles and their functions. The organelles that are often associated with storage include vacuoles, lysosomes, and vesicles.

4. **Focus on Vacuoles**: Among these, vacuoles are specifically known for their role in storage. They can store water, nutrients, and waste products.

5. **Differentiate Between Animal and Plant Cells**:
- In animal cells, vacuoles are generally smaller and fewer in number.
- In plant cells, there is typically a large central vacuole that can occupy a significant portion of the cell's volume (up to 90%).

6. **Membrane of the Vacuole**: The vacuole is surrounded by a membrane known as the tonoplast, which regulates the movement of substances in and out of the vacuole.

7. **Conclusion**: Based on the functions and characteristics discussed, the cell structure that stores water, sap, excretory products, and other non-useful materials is the **vacuole**.

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