In which of the following the cell wall has stiff cellulose plate on the outer surface-

Options

A. Dinoflagellates
B. Desmids
C. Diatoms
D. Euglenoids

Answer

To solve the question regarding which organism has a cell wall with stiff cellulose plates on the outer surface, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for an organism that has a cell wall featuring stiff cellulose plates on its outer surface.

2. **Review the Options**: The options provided are:
- A) Dinoflagellate
- B) Dasmide
- C) Diatom
- D) Euglenoid

3. **Analyze Each Option**:
- **Dinoflagellate**: These are microscopic algae known for their unique cell structure. They possess a cell wall that has stiff cellulose plates on the outer surface.
- **Dasmide**: This term is not commonly used in biological classification and does not refer to a known group with cellulose plates.
- **Diatom**: Diatoms have a silica-based cell wall, not cellulose.
- **Euglenoid**: Euglenoids have a flexible pellicle rather than a rigid cell wall made of cellulose.

4. **Identify the Correct Answer**: Based on the analysis, Dinoflagellates are the only organisms listed that have a cell wall with stiff cellulose plates on the outer surface.

5. **Conclusion**: Therefore, the correct answer to the question is **A) Dinoflagellate**.