Fertile cells are not enclosed by sterile cells in the group :-

Options

A. Thallophyta
B. Spermatophyta
C. Pteridophyta
D. Bryophyta

Answer

To solve the question "Fertile cells are not enclosed by sterile cells in the group:", we need to analyze the options provided and understand the characteristics of each group mentioned.

### Step-by-step Solution:

1. **Understand the Question**: The question is asking which group of plants has fertile cells that are not surrounded or enclosed by sterile cells. This means we are looking for a group where the reproductive cells are freely available and not protected by other non-reproductive cells.

2. **Evaluate Thalophyta**:
- Thalophyta includes algae and is characterized by a simple structure without differentiation into roots, stems, and leaves.
- In Thalophyta, the thallus (the body of the plant) can produce gametes directly.
- Since there is no differentiation, all cells can be considered fertile and are not enclosed by sterile cells.
- **Conclusion**: This option is correct.

3. **Evaluate Spermatophyta**:
- Spermatophyta refers to seed-producing plants (gymnosperms and angiosperms).
- In these plants, fertile cells (like pollen grains and ovules) are enclosed within sterile structures (like flowers and cones).
- **Conclusion**: This option is incorrect.

4. **Evaluate Tridophyta**:
- Tridophyta includes ferns and similar plants.
- In these plants, the sporangia (where spores are produced) are usually surrounded by sterile leaves or structures.
- **Conclusion**: This option is also incorrect.

5. **Evaluate Bryophyta**:
- Bryophyta includes mosses and liverworts.
- In these plants, the sporophyte generation is dependent on the gametophyte and is often enclosed in a protective structure.
- **Conclusion**: This option is incorrect as well.

6. **Final Conclusion**: After evaluating all options, the only group where fertile cells are not enclosed by sterile cells is Thalophyta. Therefore, the correct answer is **Option 1: Thalophyta**.