In an old tree trunk of mango , which tissue will be present in the maximum amount ?

Options

A. Primary xylem
B. Primary phloem
C. Secondary xylem
D. Secondary cortex

Answer

To determine which tissue is present in the maximum amount in an old mango tree trunk, we can analyze the types of tissues involved and their roles in plant growth.

### Step-by-Step Solution:

1. **Understanding Plant Tissues**:
- Plants have various tissues, but the main ones involved in transport are xylem and phloem.
- Xylem is responsible for water and mineral transport from roots to leaves, while phloem transports sugars and nutrients.

2. **Types of Xylem and Phloem**:
- Both xylem and phloem can be classified into primary and secondary types.
- Primary xylem and phloem are formed during the initial growth of the plant from the apical meristem.
- Secondary xylem and phloem are formed later from the vascular cambium, which is responsible for the thickening of the plant.

3. **Growth of the Tree**:
- As the tree ages, the amount of secondary xylem increases significantly due to continuous growth and the activity of the vascular cambium.
- In contrast, primary xylem and phloem do not increase in amount as the tree ages; they are established early in the plant's life.

4. **Analyzing the Options**:
- **Option A: Primary Xylem** - Not the maximum as it is formed early and does not increase significantly.
- **Option B: Primary Phloem** - Similar to primary xylem, it does not increase in amount.
- **Option C: Secondary Xylem** - This is formed later and increases in amount as the tree grows older.
- **Option D: Secondary Cortex** - While present, it does not have a significant increase compared to secondary xylem.

5. **Conclusion**:
- In an old mango tree trunk, the tissue present in the maximum amount is **Option C: Secondary Xylem**. This is due to its continuous formation and accumulation over the years as the tree grows.