Which organisms have silica in their cell wall?

Options

A. Dinoflagellates
B. Slime mould
C. Diatoms
D. Euglenoids

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which organisms have silica in their cell wall. This requires knowledge of different groups of organisms and their cellular structures.

2. **Identifying the Options**: The given options are:
- Dinoflagellates
- Slime molds
- Diatoms
- Euglenoids

3. **Analyzing Each Option**:
- **Dinoflagellates**: These organisms have a cell wall primarily made of cellulose, not silica.
- **Slime molds**: Slime molds also do not have silica in their cell walls; they typically have a cell wall made of cellulose or are amorphous.
- **Diatoms**: Diatoms are a group of microscopic protists known for their unique cell walls made of silica. Their cell walls are composed of many vesicles that form intricate structures called frustules.
- **Euglenoids**: Euglenoids, such as Euglena, lack a true cell wall. Instead, they have a flexible pellicle.

4. **Conclusion**: Based on the analysis, the only organisms among the options that have silica in their cell wall are diatoms.

5. **Final Answer**: The correct option is **diatoms**.

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