Callose plug and p-proteins are associated with

Options

A. Companion cells
B. Sieve tube
C. Phloem parenchyma
D. Trachea

Answer

**Step-by-Step Solution:**

1. **Understanding the Terms**: Callose plugs and P-proteins are specialized structures found in certain plant cells. Callose is a polysaccharide that forms a gel-like substance, while P-proteins are known as phloem proteins.

2. **Identifying the Context**: Both callose plugs and P-proteins are primarily associated with the phloem, which is responsible for the transport of nutrients and food produced in the leaves to other parts of the plant.

3. **Recognizing the Function**: The main role of callose plugs and P-proteins is to act as a damage control mechanism in the phloem. When there is injury to the sieve tubes, callose plugs can form to seal the damaged area, preventing loss of sap and maintaining the integrity of the transport system.

4. **Locating the Correct Cell Type**: The sieve tube elements are the specific cells in the phloem where callose plugs and P-proteins are found. They are responsible for the conduction of food and are crucial for the plant's vascular system.

5. **Eliminating Other Options**:
- Companion cells are associated with sieve tubes but do not contain callose plugs or P-proteins.
- Phloem parenchyma serves as storage and transfer cells but is not directly involved with callose plugs or P-proteins.
- Trachea are part of the xylem, which is responsible for water transport, and are not related to the phloem.

6. **Conclusion**: Based on the above analysis, the correct answer to the question is that callose plugs and P-proteins are associated with **sieve tube elements**.

**Final Answer**: Sieve tube elements.

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