Archegonium is absent in

Options

A. Bryophytes
B. Pteridophyta
C. Thallophyta
D. Gymnosperms.

Answer

To answer the question "Archegonium is absent in which of the following?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of Archegonium**:
- Archegonium is the female reproductive structure found in certain plant groups. It is responsible for producing the female gamete (egg) and is a part of the gametophyte generation.

2. **Identify Groups with Archegonium**:
- Archegonia are present in several groups of plants:
- **Bryophytes**: These include mosses and liverworts, which have a flask-shaped archegonium.
- **Pteridophytes**: This group includes ferns and horsetails, which also possess archegonia.
- **Gymnosperms**: These are seed-producing plants like conifers that have archegonia as well.

3. **Determine Where Archegonium is Absent**:
- The question asks where archegonium is absent.
- **Thallophyta** (which includes algae) is the group where archegonium is not found. Algae are classified into three main types: red algae, green algae, and brown algae, none of which have archegonia.

4. **Conclusion**:
- Based on the above analysis, the correct answer to the question is that Archegonium is absent in **Thallophyta** (algae).

### Final Answer:
- Archegonium is absent in **Thallophyta**.

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