In xylem, the ascent of sap takes place in

Options

A. Tracheids with associated xylem parenchyma
B. Walls of tracheary elements
C. Xylem perenchyme
D. Lumen of tracheary elements

Answer

**Step-by-Step Solution:**

1. **Understanding the Ascent of Sap**: The ascent of sap refers to the upward movement of water and dissolved minerals from the roots to the aerial parts of the plant. This process is crucial for the plant's survival and growth.

2. **Role of Xylem**: Xylem is the vascular tissue responsible for the conduction of water and minerals in plants. It consists of various types of cells, including tracheids and vessel elements, which facilitate this transport.

3. **Components of Xylem**: In xylem, the main components involved in the ascent of sap are:
- Tracheids: Long, narrow cells that help in the conduction of water.
- Vessel elements: Wider cells that allow for more efficient water transport.
- Xylem parenchyma: Living cells that can store nutrients and help in the transport process.

4. **Identifying the Correct Option**: The question asks where the ascent of sap takes place within the xylem. The key point is that the actual movement of sap occurs through the lumen of the tracheary elements (tracheids and vessel elements), not through the walls or associated parenchyma.

5. **Conclusion**: Therefore, the correct answer to the question is that the ascent of sap takes place in the **lumen of tracheary elements**.

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