Soap box like cell wall is characteristic of :-

Options

A. Protistans found in marine as well as fresh water environment
B. Protists which are saprophytic
C. Protists which release toxins
D. Protists which have flexible body

Answer

**Step-by-Step Solution:**

1. **Identify the Characteristic**: The question asks about the "soap box-like cell wall." This is a specific feature that we need to associate with a particular group of organisms.

2. **Recall the Organism**: The soap box-like cell wall is characteristic of diatoms. Diatoms are a type of algae that possess unique cell wall structures.

3. **Describe the Structure**: Diatoms have two thin overlapping shells that fit together, resembling a soap box. This structure is crucial for their identification.

4. **Material Composition**: The cell walls of diatoms are embedded with silica, which makes them indestructible. This is an important detail that supports the identification of diatoms.

5. **Classification**: Diatoms belong to the kingdom Protista and are classified under the group called chrysophytes. This classification helps in understanding their ecological role.

6. **Habitat**: Diatoms are found in both freshwater and marine environments. They are microscopic and can float in water currents, similar to plankton.

7. **Photosynthetic Nature**: Most diatoms are photosynthetic, which is a key feature of their biology.

8. **Evaluate the Options**: Based on the characteristics of diatoms, we can evaluate the options provided in the question. The correct option will be the one that mentions protists found in marine as well as freshwater environments.

9. **Conclusion**: The correct answer to the question is that the soap box-like cell wall is characteristic of diatoms, which belong to the chrysophytes in the kingdom Protista.

**Final Answer**: Diatoms (characterized by a soap box-like cell wall) belong to the group called chrysophytes in the kingdom Protista.

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