The cell wall is usually composed of three layers ………….., ……... and ………….

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the three layers that compose the cell wall. It is important to note that the cell wall is a structure found in plant cells.

2. **Identifying the Layers**: The cell wall is typically composed of three distinct layers:
- **Primary Cell Wall**: This is the first layer that is formed during cell division. It is flexible and allows for cell growth.
- **Middle Lamella**: This layer is found between the primary walls of adjacent cells. It is primarily made of pectin and serves as a glue to hold cells together.
- **Secondary Cell Wall**: This layer is formed after the primary wall and is thicker and more rigid. It provides additional strength and support to the cell.
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