Oogonia of Thallophyta differs with archegonia of bryophyta :-

Options

A. Being multicellular
B. Being jacketed
C. Being stallked
D. Being unicellular and jacket less

Answer

To compare the oogonia of Thallophyta with the archegonia of Bryophyta, we can analyze them based on the characteristics provided in the question: multicellularity, jacket presence, stalk presence, and unicellularity.

### Step-by-Step Solution:

1. **Definition of Oogonia and Archegonia**:
- Oogonia are the female reproductive structures found in Thallophyta, which include simple organisms like algae.
- Archegonia are the female reproductive structures found in Bryophyta, which are more advanced and include mosses and liverworts.

2. **Multicellularity**:
- Oogonia are typically unicellular structures. They are simple and do not have a complex structure.
- Archegonia, on the other hand, are multicellular structures. They consist of multiple cells organized to perform specific functions.

**Conclusion**: Oogonia are unicellular, while archegonia are multicellular.

3. **Presence of Jacket**:
- A "jacket" refers to a layer of sterile cells that protect the reproductive organs from environmental stress.
- Oogonia do not have a protective jacket; they are jacketless.
- Archegonia, however, are jacketed, meaning they have a protective layer surrounding them.

**Conclusion**: Oogonia are jacketless, while archegonia are jacketed.

4. **Presence of Stalk**:
- Stalks are structures that connect reproductive organs to the main plant body.
- Oogonia do not have a stalk; they are directly formed on the thallus of the Thallophyte.
- Archegonia also do not have a stalk; they are flask-shaped and not connected to the main plant body by a stalk.

**Conclusion**: Both oogonia and archegonia lack stalks.

5. **Unicellularity and Jacketlessness**:
- Oogonia are unicellular and jacketless, which aligns with the characteristics mentioned.
- Archegonia are multicellular and jacketed, which does not align with the characteristics of oogonia.

**Final Conclusion**: The correct option that describes the differences is that oogonia are unicellular and jacketless, while archegonia are multicellular and jacketed.

### Answer:
The oogonia of Thallophyta differ from the archegonia of Bryophyta in that oogonia are unicellular and jacketless, while archegonia are multicellular and jacketed.