Desert plants have :

Options

A. Thick cuticle
B. Sunken stomata
C. CAM pathway
D. All of these

Answer

**Step-by-Step Solution:**

1. **Understanding Desert Plants**: Desert plants, also known as xerophytes, are specialized plants that have adapted to survive in hot and dry environments. They have developed various features to minimize water loss and maximize water retention.

2. **Thick Cuticle**: One of the adaptations of desert plants is having a thick cuticle. The cuticle is a waxy layer on the epidermis of the plant that helps prevent water loss through evaporation. In desert conditions, where evaporation rates are high, a thick cuticle is essential for survival.

3. **Sunken Stomata**: Another adaptation is the presence of sunken stomata. Stomata are small openings on the leaves that allow for gas exchange. In desert plants, these stomata are often sunken, which reduces the exposure to air and minimizes water loss through transpiration. This adaptation is crucial for conserving water in arid conditions.

4. **CAM Pathway**: Desert plants often utilize a specialized photosynthetic pathway known as Crassulacean Acid Metabolism (CAM). In this process, the stomata open at night to take in carbon dioxide, which is then stored as malic acid. During the day, the stomata remain closed to prevent water loss, and the stored carbon dioxide is used for photosynthesis. This adaptation allows desert plants to thrive in conditions where water is scarce.

5. **Conclusion**: Given the adaptations discussed (thick cuticle, sunken stomata, and CAM pathway), all of these features are characteristic of desert plants. Therefore, the correct answer to the question "Desert plants have:" is "all of these."

**Final Answer**: All of these.

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