`CO_(2)` is liberated during

Options

A. Ascent of sap
B. Respiration
C. Photosynthesis
D. Transpiration

Answer

To answer the question "CO₂ is liberated during," we will analyze each of the given options step by step.

### Step-by-Step Solution:

1. **Ascent of Sap**:
- The ascent of sap occurs in the xylem tissue of plants.
- It involves the upward movement of water and minerals from the roots to the upper parts of the plant.
- During this process, there is no release of carbon dioxide (CO₂).
- **Conclusion**: This option is incorrect.

2. **Respiration**:
- Respiration is an enzyme-controlled process of oxidation.
- It involves the breakdown of food, consuming oxygen and producing carbon dioxide as a byproduct.
- Energy released during respiration is stored in the form of ATP.
- **Conclusion**: This option is correct as CO₂ is liberated during respiration.

3. **Photosynthesis**:
- Photosynthesis is the process by which plants convert light energy into chemical energy.
- In this process, carbon dioxide is utilized, and oxygen is produced.
- Therefore, CO₂ is not liberated; instead, it is consumed.
- **Conclusion**: This option is incorrect.

4. **Transpiration**:
- Transpiration refers to the evaporation of water from the aerial parts of the plant, such as leaves and stems.
- It involves the movement of water through the plant but does not involve the production of carbon dioxide.
- **Conclusion**: This option is incorrect.

### Final Answer:
CO₂ is liberated during **respiration**.

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