PSI Barbering Practice Exam

The epidermis contains no ________, but has many small nerve endings.

1. Blood vessels

2. Nerve fibers

3. Hair follicles

4. Sweat glands

The correct answer is: Blood vessels

The epidermis is the outermost layer of skin, and one of its defining characteristics is the absence of blood vessels. This layer primarily relies on diffusion from underlying tissues for nutrient exchange and waste removal. Because it does not contain blood vessels, it creates a protective barrier that limits direct blood supply, which is one of the reasons why wounds in the epidermis heal relatively quickly and are less prone to heavy bleeding compared to deeper layers of the skin. While the epidermis does contain many small nerve endings, which are responsible for sensations such as touch and temperature, it does not require blood vessels to fulfill its primary functions, as it is supported by the dermis beneath. The presence of sweat glands and hair follicles is found within the dermis and not specifically in the epidermis, reinforcing the idea that the epidermis itself is avascular (lacking blood vessels).