What are three layers of cell envelope of a bacterium?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Cell Envelope**: The cell envelope of a bacterium consists of three distinct layers that provide structure and protection to the bacterial cell.

2. **Identifying the First Layer - Glycocalyx**: The outermost layer of the cell envelope is called the glycocalyx. This layer is composed of a coating of mucus or polysaccharide material. Its primary functions include protecting the cell and aiding in adhesion to surfaces or other cells.

3. **Identifying the Second Layer - Cell Wall**: The second layer is the cell wall. The cell wall is crucial as it determines the shape of the bacterial cell and provides strong structural support. It helps maintain the integrity of the cell under various environmental conditions.

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