Calcium is mainly a component of

Options

A. primary walls
B. secondary wall
C. chlorophyll
D. middle lamella

Answer

**Step-by-Step Solution:**

1. **Identify the Question:** The question asks about the main component of calcium among the given options: primary walls, secondary walls, chlorophyll, or middle lamella.

2. **Evaluate the Options:**
- **Primary Walls:** These are primarily composed of cellulose and hemicellulose. Calcium is not a major component here.
- **Secondary Walls:** Similar to primary walls, secondary walls are also made up of cellulose and hemicellulose. Thus, calcium is not a significant component in this structure either.
- **Chlorophyll:** Chlorophyll is primarily composed of nitrogen, magnesium, and other elements, but does not contain calcium as a main component.
- **Middle Lamella:** The middle lamella is primarily composed of calcium pectate, which plays a crucial role in binding cells together.

3. **Conclusion:** Based on the evaluation of the options, calcium is mainly a component of the middle lamella.

4. **Final Answer:** Calcium is mainly a component of the middle lamella.

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