Soap box-like overlapping shells are found in the cell walls of

Options

A. dinoflagellates
B. protozoan
C. diatoms
D. euglenoids

Answer

To solve the question regarding which organism has soap box-like overlapping shells in their cell walls, we will analyze each option provided in the question step by step.

### Step-by-Step Solution:

1. **Understanding the Question**:
- The question asks about the presence of soap box-like overlapping shells in the cell walls of certain organisms.

2. **Analyzing Option A: Dinoflagellates**:
- Dinoflagellates have a cell wall structure known as theca, which is membrane-bound.
- The theca is divided into plates but does not exhibit a soap box-like structure.
- **Conclusion**: This option is incorrect.

3. **Analyzing Option B: Protozoans**:
- Protozoans typically do not have a rigid cell wall like plants; instead, they have a flexible cell membrane.
- Some protozoans may have structures like trabeculae, but they do not have overlapping shells.
- **Conclusion**: This option is also incorrect.

4. **Analyzing Option C: Diatoms**:
- Diatoms possess a unique cell wall structure known as a frustule.
- The frustule consists of two thin overlapping shells that fit closely together, resembling a soap box-like structure.
- **Conclusion**: This option is correct.

5. **Analyzing Option D: Eucalyptus**:
- Eucalyptus is a plant and does not have a cell wall structure similar to the soap box-like shells.
- Instead, it has a typical plant cell wall made of cellulose.
- **Conclusion**: This option is incorrect.

### Final Answer:
The correct answer is **C: Diatoms**.

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