Explanation:

Introduction:
Xerophytes are plants that have adapted to survive in dry and arid conditions. They have evolved various characteristics to minimize water loss and maximize water uptake. Some of these adaptations include reduced leaves, sunken stomata, and the ability to perform CAM (Crassulacean Acid Metabolism). However, one characteristic that should not be present in any xerophyte is the absence of the cuticle.

Explanation:

The cuticle:
The cuticle is a waxy layer that covers the surface of leaves and stems. It acts as a barrier to prevent water loss by reducing transpiration. The cuticle is made up of a lipid layer called cutin, which is impermeable to water. This helps to retain water within the plant and protect it from desiccation.

Importance of the cuticle:
The cuticle plays a vital role in the survival of plants in dry environments. It reduces the rate of water loss through transpiration by acting as a physical barrier. In xerophytes, the cuticle is often thicker and more pronounced than in mesophytes (plants adapted to moderate moisture conditions). This helps to prevent excessive water loss in xerophytes, allowing them to survive in arid environments.

Why absence of cuticle should not be a characteristic feature of xerophytes:
The absence of the cuticle in xerophytes would result in increased transpiration and water loss. This would be detrimental to the survival of xerophytes in dry conditions, as it would lead to rapid dehydration and desiccation. The cuticle acts as a protective layer, reducing water loss and helping xerophytes to conserve water. Therefore, the absence of the cuticle would be counterproductive and not a characteristic feature of xerophytes.

Conclusion:
In summary, xerophytes are plants that have adapted to survive in dry environments. They possess various adaptations to minimize water loss and maximize water uptake. While characteristics such as reduced leaves, sunken stomata, and CAM are common in xerophytes, the absence of the cuticle should not be a characteristic feature. The cuticle plays a crucial role in reducing water loss through transpiration and helps xerophytes to conserve water in arid conditions.