The epidermis receives blood containing oxygen and nutrients from which of the following?

• A. Capillaries within the epidermis
• B. The dermal blood vessels
• C. Lymphatic vessels in the epidermis
• D. Sebaceous glands

Answer: (B)

Verified step by step guidance

1. Understand the structure of the skin: The skin is composed of two main layers, the epidermis (outer layer) and the dermis (inner layer). The epidermis is avascular, meaning it does not contain blood vessels.
2. Recognize the role of the dermis: The dermis contains blood vessels, which supply oxygen and nutrients to the epidermis through diffusion. This is because the epidermis relies on the dermal blood vessels for nourishment.
3. Eliminate incorrect options: Capillaries within the epidermis cannot be correct because the epidermis lacks blood vessels. Similarly, lymphatic vessels and sebaceous glands do not supply oxygen and nutrients to the epidermis.
4. Focus on diffusion: Nutrients and oxygen from the dermal blood vessels diffuse upward into the avascular epidermis to maintain its cells, particularly the basal layer where cell division occurs.
5. Conclude the correct answer: Based on the anatomy and physiology of the skin, the dermal blood vessels are responsible for supplying oxygen and nutrients to the epidermis.