Explain the significance of the cuticle on the epidermal layer of plants.

The cuticle is a waxy, waterproof layer secreted by the epidermal cells on the outer surface of plant parts, especially leaves and stems. Its significance lies primarily in preventing excessive water loss through transpiration, particularly in terrestrial plants. It acts as a protective barrier against desiccation, mechanical injury, and pathogen entry. The thickness of the cuticle can vary depending on the plant's habitat, being thicker in plants adapted to dry environments.