Which one of the following is a characteristic feature of Chrysophytes

Options

A. Parasitic forms causing diseases in animals
B. Have protein rich layer called pellicle
C. Commonly called dinoflagellates
D. Have indestructible wall layer deposited with silica.

Answer

To determine the characteristic feature of Chrysophytes, let's analyze the options provided step by step.

### Step-by-Step Solution:

1. **Understanding Chrysophytes**:
- Chrysophytes are a group of plant-like protists, primarily autotrophic, meaning they can produce their own food through photosynthesis. They are found in both marine and freshwater environments.

2. **Identifying Types of Chrysophytes**:
- The main types of chrysophytes include yellow-green algae, golden-brown algae, and diatoms.

3. **Evaluating the Options**:
- **Option A**: "Parasitic forms causing diseases in animals" - This is incorrect because chrysophytes are not known to be parasitic.
- **Option B**: "Have protein-rich layer called pellicle" - This is also incorrect; chrysophytes do not have a pellicle.
- **Option C**: "Commonly called as dinoflagellates" - This is incorrect as dinoflagellates are a separate group of protists and not synonymous with chrysophytes.
- **Option D**: "They have indestructible wall layer deposited with silica" - This is correct. Chrysophytes, particularly diatoms, have a cell wall made of silica, which is a distinctive feature of this group.

4. **Conclusion**:
- The characteristic feature of chrysophytes is that they have an indestructible wall layer deposited with silica. Therefore, the correct answer is **Option D**.