Middle lamella is mainly composed of:-

Answer

### Step-by-Step Solution

1. **Understanding Middle Lamella**: The middle lamella is a layer that exists between the cell walls of two adjacent plant cells. It plays a crucial role in holding these cells together.

2. **Composition of Middle Lamella**: The primary components of the middle lamella are substances known as pectins. These are polysaccharides that are rich in galacturonic acid.

3. **Function of Pectins**: Pectins serve as a cementing material between the cell walls of adjacent cells. They help in maintaining the structural integrity of plant tissues.

4. **Specific Types of Pectins**: Among the various types of pectins, calcium pectate and magnesium pectate are significant. These compounds are formed when pectin molecules bind with calcium and magnesium ions, respectively.

5. **Formation of Plasmodesmata**: The middle lamella also plays a role in the formation of plasmodesmata, which are microscopic channels that allow for communication and transport of substances between adjacent cells.

6. **Conclusion**: Therefore, the middle lamella is mainly composed of calcium pectate and magnesium pectate.

### Final Answer
The middle lamella is mainly composed of calcium pectate and magnesium pectate.

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