During differentiation of xylem

Options

A. End walls are lost in tracheids
B. Loss of protoplasm occurs in vessels
C. Lignified thikening develop in tracheary elements
D. More than one option is correct

Answer

### Step-by-Step Text Solution:

1. **Understanding Xylem**:
- Xylem is a complex vascular tissue in plants responsible for the transportation of water and dissolved minerals from the roots to the rest of the plant.

2. **Differentiation Process**:
- Differentiation refers to the process by which cells mature and develop specialized functions. In the case of xylem, this involves the maturation of its various components.

3. **Components of Xylem**:
- The main components of xylem include:
- Xylem tracheids
- Xylem vessels
- Xylem fibers
- Xylem parenchyma

4. **Lignification**:
- During differentiation, the tracheids and vessels undergo lignification, where lignin is deposited in their cell walls, making them strong and water-resistant.

5. **Protoplast Disappearance**:
- As xylem cells mature, the protoplast (the living part of the cell) is lost. This is particularly noted in the xylem vessels, where the protoplast breaks down and disappears.

6. **Conclusion**:
- Based on the differentiation process of xylem, we can conclude that:
- The tracheids develop lignified thickening.
- The protoplast is lost in the vessels.
- Therefore, more than one option is correct in the context of xylem differentiation.

### Final Answer:
During the differentiation of xylem, the tracheids develop lignified thickening, and the protoplast is lost in the vessels. Hence, more than one option is correct.

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