Which of the following group members possess cell wall with stiff cellulose plates on its outer surface ?

Options

A. Chrysophytes
B. Euglenoids
C. Dinoflagellates
D. Slime moulds

Answer

To solve the question regarding which group members possess a cell wall with stiff cellulose plates on its outer surface, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks which group of organisms has a cell wall characterized by stiff cellulose plates on the outer surface.

2. **Analyze Each Option**:
- **Option 1: Diatoms**: Diatoms have a cell wall made of silica, not cellulose. Therefore, this option is incorrect.
- **Option 2: Euglenoids**: Euglenoids do not possess a traditional cell wall. Instead, they have a pellicle, which is a flexible proteinaceous layer. Thus, this option is also incorrect.
- **Option 3: Dinoflagellates**: Dinoflagellates are known to have cell walls that contain stiff cellulose plates. This aligns with the requirement of the question, making this option a potential correct answer.
- **Option 4: Slime Molds**: Slime molds do have a cell wall, but it is primarily made of cellulose and does not have the characteristic stiff cellulose plates mentioned in the question. Therefore, this option is incorrect.

3. **Conclusion**: After analyzing all the options, the correct answer is **Option 3: Dinoflagellates**, as they possess cell walls with stiff cellulose plates on their outer surface.

### Final Answer:
**Dinoflagellates** (Option 3) possess cell walls with stiff cellulose plates on their outer surface.

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