Chief functions of leaves are

Options

A. Transpiration and photosynthesis
B. Respiration and photosynthesis
C. Respiration and digestion
D. Respiration and transpiration.

Answer

### Step-by-Step Solution:

1. **Identify the Chief Functions of Leaves**: The primary functions of leaves are transpiration and photosynthesis.

2. **Explain Transpiration**: Transpiration is the process through which water is lost from the leaves in the form of water vapor. This process helps in regulating temperature and maintaining the flow of nutrients and water from the roots to the leaves.

3. **Differentiate Guttation from Transpiration**: Guttation is often confused with transpiration. While transpiration involves the loss of water vapor, guttation refers to the loss of water in the form of droplets, usually occurring at night when the humidity is high.

4. **Explain Photosynthesis**: Photosynthesis is the process by which leaves convert light energy into chemical energy, using carbon dioxide and water, and producing glucose and oxygen as by-products. This process primarily occurs in the chlorophyll, which is the green pigment found in the chloroplasts of leaf cells.

5. **Location of Chlorophyll**: Chlorophyll is located in the thylakoid membranes of the chloroplasts within leaf cells, where the light-dependent reactions of photosynthesis take place.

### Summary:
The chief functions of leaves are:
- **Transpiration**: Loss of water vapor from leaves.
- **Photosynthesis**: Conversion of light energy into chemical energy, occurring in chlorophyll located in the thylakoid membranes.

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