What gives the dermis its solidity?

The dermis is primarily composed of elastic and collagen fibers, which are essential for its structural integrity. Collagen fibers provide strength and resilience, allowing the dermis to withstand tension and stress while maintaining its shape. Elastic fibers contribute to the dermis's ability to stretch and return to its original form, which is crucial for flexibility and adaptability of the skin.

Muscle fibers, while present in the skin, are primarily found in the surrounding structures, such as the arrector pili muscles that cause hair to stand up. Epithelial cells form the outer layer of the skin, the epidermis, and do not contribute to the solidity of the dermis. Sebaceous secretions are related to lubrication and protection of the skin, but they do not play a role in providing structural support to the dermis. Hence, the combination of elastic and collagen fibers is what ultimately gives the dermis its solidity and functional characteristics.