Final answer:
The outer surface of the primary developmental cuticle in plants is covered with a waxy layer that helps prevent water loss, while in arthropods, this surface is part of the exoskeleton which includes a thin, water-resistant epicuticle. It acts as a barrier to water and gases, reducing transpiration and providing protection from environmental stresses.
Step-by-step explanation:
The outer surface of the primary developmental cuticle in plants is covered with a waxy layer known as the cuticle. In arthropods, the cuticle is part of the exoskeleton, consisting of two layers: the epicuticle and the procuticle, which is made up of the exocuticle and the endocuticle. The epicuticle is a thin, waxy, and water-resistant outer layer that helps prevent water loss and provides protection from the environment without compromising flexibility or mobility. The epicuticle is a thin, waxy, water-resistant outer layer that does not contain chitin. It provides protection against dehydration and other biological and physical stresses.
The cuticle is secreted by the epidermis cells, forming a barrier that is impermeable to water and gases, thereby reducing transpiration and protecting against dehydration and other stresses. In contrast, the epidermis of the skin is protected by a collagenous cuticle, which does not require shedding for growth. Hairs, or trichomes, may also be present on the epidermis of plants, providing additional protection against herbivory and water loss.