Pit pairs allow plasmodesmata to travel through -

Options

A. The primary cell wall
B. The secondary cell wall
C. Both the primary and secondary cell wall
D. Neither primary nor secondary cell wall

Answer

To answer the question "Pit pairs allow plasmodesmata to travel through," we need to analyze the options provided and understand the structure and function of pit pairs and plasmodesmata in plant cells.

### Step-by-Step Solution:

1. **Understanding Plasmodesmata**:
- Plasmodesmata are microscopic channels that traverse the cell walls of plant cells. They facilitate communication and transport of substances between adjacent cells.

2. **Understanding Pit Pairs**:
- Pit pairs are specialized structures in the cell wall where two adjacent cells have thin areas that allow for the passage of plasmodesmata. These pits are formed in the primary and secondary cell walls.

3. **Types of Cell Walls**:
- **Primary Cell Wall**: This is the first layer of the cell wall formed during cell division. It is flexible and allows for cell growth.
- **Secondary Cell Wall**: This is formed after the primary wall and is usually thicker and more rigid, providing additional support and protection.

4. **Analyzing the Options**:
- **Option 1: Primary Cell Wall**: This option suggests that plasmodesmata can travel through only the primary cell wall.
- **Option 2: Secondary Cell Wall**: This option suggests that plasmodesmata can travel through only the secondary cell wall.
- **Option 3: Primary and Secondary Cell Wall**: This option suggests that plasmodesmata can travel through both types of cell walls.
- **Option 4: Neither Primary nor Secondary Cell Wall**: This option suggests that plasmodesmata do not travel through either type of cell wall.

5. **Conclusion**:
- Since plasmodesmata can indeed traverse through both primary and secondary cell walls via pit pairs, the correct answer is **Option 3: Primary and Secondary Cell Wall**.

### Final Answer:
Pit pairs allow plasmodesmata to travel through **both primary and secondary cell walls**.

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