What layer of skin contains capillaries, nerve endings, sweat glands, and hair follicles?

The dermis is the layer of skin that is situated beneath the epidermis and is rich in structural and functional components. It contains capillaries, which are small blood vessels that supply oxygen and nutrients to the skin while aiding in thermoregulation. The presence of nerve endings is also crucial, as these structures are responsible for the sensation of touch, pain, temperature, and pressure.

Additionally, the dermis houses sweat glands, which are essential for regulating body temperature and excreting certain waste products through perspiration. Hair follicles, which are responsible for hair growth, also reside in this layer, embedded within the dermis. This layer is thicker than the epidermis and provides strength and elasticity to the skin via collagen and elastin fibers.

In contrast, the epidermis is primarily the outermost protective layer without these structures, while the hypodermis, also known as the subcutaneous layer, serves to anchor the skin to underlying tissues and organs, primarily consisting of fat and connective tissue. This distinction helps clarify why the dermis is the correct answer, as it plays a vital role in the skin's overall functionality and health.