Transpiration in plants is

Options

A. not very important
B. immaterial for them
C. a serious burden
D. a necessary evil

Answer

**Step-by-Step Solution:**

1. **Understanding Transpiration**:
- Transpiration is defined as the process through which plants lose water in the form of water vapor. This occurs primarily through small openings on the leaves known as stomata.

2. **Mechanism of Transpiration**:
- The water vapor exits the plant through the stomata, which creates a negative pressure (or pull) within the plant. This pull is essential for the absorption of water from the roots and its movement (translocation) through the plant.

3. **Functions of Transpiration**:
- Transpiration serves several important functions:
- It helps maintain water balance within the plant.
- It regulates the temperature of the plant, providing a cooling effect.
- It supports growth and development by facilitating nutrient transport.

4. **Transpiration as a Necessary Evil**:
- While transpiration is crucial for plant health, it can also lead to unnecessary water loss. This dual nature is why it is often referred to as a "necessary evil." It creates a pressure that aids in water absorption but can also result in excessive water loss.

5. **Evaluating Options**:
- Given the options provided:
- Option A: "Not very important" - Incorrect, as transpiration is vital for plants.
- Option B: "Immaterial for them" - Incorrect, as it plays a crucial role.
- Option C: "A serious burden" - Incorrect, as it is beneficial despite some drawbacks.
- Option D: "A necessary evil" - Correct, as it encapsulates both the benefits and drawbacks of transpiration.

6. **Conclusion**:
- The correct answer to the question about transpiration in plants is Option D: "A necessary evil."

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