Diatoms stay afloat due to

Options

A. Pseudopodia
B. Flagella
C. Stored lipids
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Diatoms**: Diatoms are a type of unicellular algae that belong to the kingdom Protista. They are known for their unique silica cell walls and play a significant role in aquatic ecosystems.

2. **Question Analysis**: The question asks why diatoms stay afloat in water. The options provided are:
- A) Pseudopodia
- B) Flagella
- C) Stored lipids
- D) All of the above

3. **Evaluating the Options**:
- **Pseudopodia**: These are temporary projections of the cell membrane and cytoplasm used for movement and feeding in some protists. However, diatoms do not utilize pseudopodia for buoyancy.
- **Flagella**: These are whip-like structures that some organisms use for movement. Most diatoms are non-motile and do not possess flagella.
- **Stored Lipids**: Diatoms store lipids within their cells. These lipids are less dense than water, which increases their buoyancy and helps them remain suspended in the water column.

4. **Conclusion**: Since diatoms lack pseudopodia and flagella, the only viable option that explains their ability to stay afloat is the presence of stored lipids. Therefore, the correct answer is **C) Stored lipids**.

5. **Final Answer**: Diatoms stay afloat due to stored lipids.

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