Prothallus of Dryopteris is and bears archegonia over

Options

A. Sporophyte, dorsally
B. Sporophyte, ventrally
C. Gametophyte, dorsally
D. Gametophyte, ventrally.

Answer

To solve the question regarding the prothallus of Dryopteris and the location of archegonia, follow these steps:

### Step-by-Step Solution:

1. **Understanding Prothallus**:
- The prothallus is the gametophyte stage in the life cycle of ferns, including Dryopteris. It is a small, heart-shaped structure that is typically haploid.

2. **Identifying Archegonia**:
- Archegonia are the female reproductive structures that produce eggs. In ferns, these structures are found on the prothallus.

3. **Location of Archegonia**:
- The question asks where the archegonia are located on the prothallus of Dryopteris. It is important to note that in ferns, archegonia are located on the ventral (lower) side of the prothallus.

4. **Selecting the Correct Answer**:
- Based on the information that the prothallus is a gametophyte and that archegonia are found on the ventral side, we can conclude that the correct answer is:
- **Option D: gametophyte ventrally**.

### Final Answer:
The prothallus of Dryopteris is a gametophyte and bears archegonia on the ventral side (Option D).

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