Middle lamella mainly contains

Options

A. Ca
B. Mg
C. Na
D. K

Answer

### Step-by-Step Solution:

1. **Understanding Middle Lamella**:
- The middle lamella is a layer found between the primary cell walls of two adjacent plant cells. It acts as a glue that holds the cells together.

2. **Composition of Middle Lamella**:
- The middle lamella is primarily composed of pectins, which are polysaccharides that play a crucial role in cell adhesion.

3. **Role of Calcium in Middle Lamella**:
- Calcium is a significant component of pectins in the middle lamella. It helps in stabilizing the structure of pectins, thus providing strength to the cell wall.

4. **Presence of Magnesium**:
- Along with calcium, magnesium is also present in the middle lamella. It contributes to the overall stability and strength of the cell wall.

5. **Function of Middle Lamella**:
- The middle lamella serves to cement adjacent plant cells together, providing structural integrity and facilitating communication between cells through structures known as plasmodesmata.

6. **Conclusion**:
- The main components of the middle lamella are calcium and magnesium, with calcium being the primary element.

### Final Answer:
The middle lamella mainly contains calcium (and also magnesium).

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