Large blood vessels and lymphatic vessels are most commonly found in which layer of the integumentary system?

• A. Stratum basale of the epidermis
• B. Hypodermis (subcutaneous layer)
• C. Stratum corneum of the epidermis
• D. Papillary layer of the dermis

Answer: (B)

Verified step by step guidance

1. Understand the structure of the integumentary system, which consists of three main layers: the epidermis (outermost), the dermis (middle), and the hypodermis (subcutaneous layer, deepest).
2. Recall that the epidermis is avascular, meaning it does not contain blood vessels, so large blood vessels cannot be found in any of its layers such as the stratum basale or stratum corneum.
3. Recognize that the dermis is divided into two layers: the papillary layer (upper) and the reticular layer (lower). The papillary layer contains smaller blood vessels and capillaries but not large blood vessels.
4. Identify that the hypodermis, also called the subcutaneous layer, contains larger blood vessels and lymphatic vessels, as it connects the skin to underlying tissues and provides vascular support.
5. Conclude that large blood vessels and lymphatic vessels are most commonly found in the hypodermis (subcutaneous layer), not in the epidermis or papillary layer of the dermis.