Which element is present in the middle lamellae of cell wall?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Cell Wall Structure**: The cell wall is composed of three major layers: the primary cell wall, the middle lamella, and the secondary cell wall. Each layer has distinct functions and compositions.

2. **Identifying the Middle Lamella**: The middle lamella is the layer that acts as a cementing substance between the primary walls of adjacent cells. It is crucial for maintaining the integrity and strength of plant tissues.

3. **Composition of the Middle Lamella**: The middle lamella is primarily made up of pectins, which are polysaccharides. These pectins play a significant role in the adhesion between plant cells.

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