Transfer cells occur in

Options

A. xylem parenchyma
B. phloem parenchyma
C. epithelium
D. all the above

Answer

**Step-by-Step Solution:**

1. **Understanding Transfer Cells**: Transfer cells are specialized cells that facilitate the movement of substances, particularly nutrients and food, within plants.

2. **Identifying the Options**: The options given are:
- Xylem parenchyma
- Phloem parenchyma
- Epithelium
- All of the above

3. **Analyzing Phloem Parenchyma**: Phloem parenchyma is known for its role in the transport of food. It contains specialized cells known as transfer cells or border parenchyma cells.

4. **Location of Transfer Cells**: Transfer cells are typically found near the finest branches and terminations of sieve tubes in leaf veinlets, which are part of the phloem.

5. **Function of Transfer Cells**: The primary function of transfer cells is to aid in the transport of food substances, making them crucial for plant nutrition.

6. **Conclusion**: Based on the analysis, transfer cells specifically occur in phloem parenchyma. Therefore, the correct answer is option 2: phloem parenchyma.

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