Plant growth is unique in being

Options

A. Closed
B. Unlimited
C. Diffuse
D. Limited

Answer

**Step-by-Step Solution:**

1. **Understanding Plant Growth**: Plant growth is characterized by an irreversible and permanent increase in size. This means that once a plant grows, it cannot revert to its previous size.

2. **Characteristics of Plant Growth**: Unlike animals, plants have unique growth characteristics. They can continue to grow throughout their life due to the presence of specific cells.

3. **Role of Meristem Cells**: Plants contain meristem cells, which are undifferentiated cells that have the ability to divide and self-perpetuate. These cells are crucial for plant growth as they continuously produce new cells.

4. **Open Growth**: The type of growth exhibited by plants is known as "open growth." This means that plants can always add new cells to their structure, allowing for continuous growth.

5. **Evaluating the Options**:
- **Closed**: This option is incorrect because plant growth is not closed; it is open to continuous cell addition.
- **Unlimited**: This is the correct option as plants have the capacity for unlimited growth due to meristem cells.
- **Diffuse**: This option is incorrect as it does not accurately describe plant growth.
- **Limited**: This option is also incorrect because plants do not have limited growth potential.

6. **Conclusion**: Therefore, the correct answer to the question "Plant growth is unique in being" is **unlimited**.

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