CAM occurs in

Options

A. Thin green leaves with reticulate venation
B. Thin green leaves with parallel venation
C. Thin coloured leaves
D. Fleshy green leaves.

Answer

**Step-by-Step Solution:**

1. **Understanding CAM:** CAM stands for Crassulacean Acid Metabolism, which is a specialized form of photosynthesis that allows certain plants to adapt to arid (dry) conditions.

2. **Stomatal Behavior:** In CAM plants, the stomata (tiny openings on the leaves) remain closed during the day to minimize water loss through evapotranspiration. Instead, they open at night to take in carbon dioxide (CO2).

3. **Photosynthesis Location:** The process of photosynthesis in CAM plants primarily occurs in thick, fleshy green leaves. This adaptation helps these plants conserve water while still being able to perform photosynthesis.

4. **Analyzing Options:** The question provides four options regarding the type of leaves where CAM occurs:
- Thin green leaves with reticulate venation
- Thin green leaves with parallel venation
- Thin colorless leaves
- Fleshy green leaves

5. **Identifying the Correct Answer:** Based on the characteristics of CAM plants, the correct answer is "fleshy green leaves." The other options (thin leaves) are not suitable for CAM photosynthesis as they would not effectively conserve water.

**Final Answer:** CAM occurs in fleshy green leaves.

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