Companion cells are present alongside the

Options

A. xylem vessels
B. sieve cells
C. sieve tubes
D. tracheids

Answer

**Step-by-Step Solution:**

1. **Understanding Companion Cells**: Companion cells are specialized cells found in the phloem tissue of flowering plants. They play a crucial role in the transport of nutrients.

2. **Identifying Phloem Components**: The phloem is made up of several types of cells, including sieve tubes, companion cells, parenchyma cells, and fibers. The primary conducting cells in the phloem are the sieve tubes.

3. **Relationship Between Companion Cells and Sieve Tubes**: Companion cells are located adjacent to sieve tube elements. They have a nucleus, which is essential for the functioning of both the companion cells and the sieve tubes.

4. **Function of Companion Cells**: The nucleus of the companion cell supports the metabolic functions of the sieve tube elements, which lack a functional nucleus. This relationship is vital for the transport of organic substances throughout the plant.

5. **Evaluating the Options**: The question provides four options: xylem vessels, sieve cells, sieve tubes, and tracheids. Based on the relationship established, companion cells are specifically associated with sieve tubes.

6. **Conclusion**: Therefore, the correct answer is that companion cells are present alongside the **sieve tubes**.

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