Secondary cell wall grows by

Options

A. Deamination
B. Calcicole
C. Apposition
D. None of these

Answer

**Step-by-Step Solution:**

1. **Understanding Secondary Cell Wall**: The secondary cell wall is a structure found in plants that provides additional support and protection. It is typically formed after the primary cell wall and is thicker and more rigid.

2. **Identifying Growth Mechanisms**: To determine how the secondary cell wall grows, we need to look at the processes involved in its formation. The main processes include apposition and deamination.

3. **Deamination**: This process involves the removal of an amino group from an amino acid. While it is a biochemical process, it does not contribute directly to the growth of the secondary cell wall.

4. **Apposition**: This is the correct process for the growth of the secondary cell wall. Apposition refers to the deposition of new layers of material onto the existing cell wall, which includes the addition of lignin, a complex organic polymer that strengthens the cell wall.

5. **Conclusion**: Based on the processes discussed, the secondary cell wall grows primarily by apposition, which involves the thickening of the cell wall through the deposition of lignin and other materials.

**Final Answer**: The secondary cell wall grows by apposition.

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