Which of the following is NOT a characteristic of deep veins?

Deep veins are a critical component of the venous system, serving to return blood from the limbs back to the heart. Understanding their characteristics helps in identifying various vascular conditions and treatments.

The correct answer points out that deep veins are not located suprafascial. In fact, deep veins are situated deep within the muscles, beneath the fascia layers. They are accompanied by muscles and are surrounded by tightly bound tissue, which plays a significant role in the venous return mechanism through muscle contractions. The positioning of deep veins differs from superficial veins, which are located just beneath the skin.

In terms of wall structure, deep veins have thick walls to withstand higher pressure as they manage blood returning from the lower body. This is contrasted with superficial veins, which often have thinner walls. The term "less distention" correctly refers to the elastic nature of deep veins, which helps maintain venous tone and prevents excessive dilation under varying pressures, especially during physical activity.

Thus, recognizing that deep veins are found deeper in the tissues, rather than suprafascial (which would indicate they are just under the skin), highlights a fundamental aspect of their anatomy and physiological function.