The neck of the archegonium in Selaginella is made of

Options

A. Four rows of cells with several cells in each row
B. Two tiers of four cells each
C. Four tiers of two cells each
D. Six rows of cells.

Answer

**Step-by-Step Solution:**

1. **Understanding Archegonium Structure**: The archegonium is the female reproductive structure in plants, including Selaginella. It is essential to know its structure to answer the question correctly.

2. **Formation of Archegonium in Selaginella**: In Selaginella, the archegonium originates from a single superficial cell in the female gametophyte. This cell undergoes divisions to form the archegonium.

3. **Division of Primary Cover Cells**: The primary cover cells undergo two vertical divisions at right angles to each other, resulting in the formation of four neck initials.

4. **Formation of Neck Cells**: These neck initials further divide transversely to produce eight neck cells. This is a crucial point as it defines the structure of the neck.

5. **Arrangement of Neck Cells**: The eight neck cells are arranged in two rows, confirming that the neck of the archegonium consists of these cells.

6. **Identifying the Correct Option**: Given the options provided, we need to identify which one accurately describes the neck of the archegonium. The correct description is "two tiers of four cells each," as there are two rows of four neck cells.

7. **Conclusion**: The neck of the archegonium in Selaginella is made of two tiers of four cells each.

**Final Answer**: The neck of the archegonium in Selaginella is made of two tiers of four cells each.

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