Middle lamella is composed mainly of :

Options

A. calcium pectate
B. phosphoglycerides
C. hemicellulose
D. muramic acid

Answer

**Step-by-Step Solution:**

1. **Understanding Middle Lamella**: The middle lamella is a layer found in plant cells that acts as a cementing substance between the cell walls of adjacent cells. It is crucial for maintaining the structure and integrity of plant tissues.

2. **Composition of Middle Lamella**: The middle lamella is primarily composed of pectin, which is a polysaccharide. Pectin helps in binding cells together and provides stability to the plant structure.

3. **Identifying the Key Component**: Among the options provided (calcium pectate, phosphoglycerides, hemicellulose, metamic acid), we need to identify which one is primarily found in the middle lamella.

4. **Correct Answer**: The middle lamella is mainly composed of **calcium pectate**. This compound is a combination of pectin with calcium ions, which helps in the stabilization of the middle lamella.

5. **Conclusion**: Therefore, the correct answer to the question is that the middle lamella is composed mainly of **calcium pectate**.

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