Load bearing parts of the plant cells is

Options

A. Middle lamella
B. Secondary wall
C. Primary wall
D. Tertiary wall

Answer

To answer the question "Load bearing parts of the plant cells is", we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Components of Plant Cell Walls**:
- Plant cells have different layers in their cell walls, which include the primary wall, secondary wall, and middle lamella.

2. **Understand the Middle Lamella**:
- The middle lamella is the outermost layer of the cell wall and is primarily composed of calcium and magnesium pectate. It acts as a glue between adjacent cells but is not primarily responsible for load-bearing.

3. **Examine the Primary Cell Wall**:
- The primary wall is made up of glycoproteins and phospholipids. While it provides some structural support, it is not the main load-bearing structure.

4. **Analyze the Secondary Cell Wall**:
- The secondary wall is formed after the primary wall and is made up of cellulose, hemicellulose, and lignin. Cellulose is particularly important for providing tensile strength and rigidity, making the secondary wall the main load-bearing part of the plant cell.

5. **Consider the Tertiary Wall**:
- The tertiary wall is less common and is composed of xylans. It does not play a significant role in load-bearing compared to the secondary wall.

6. **Conclusion**:
- Based on the analysis, the load-bearing part of the plant cell is the secondary wall.

### Final Answer:
The load-bearing part of the plant cells is the **secondary wall**.

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