Which description correctly identifies the layer that anchors the vessel to surrounding tissues?

Which description correctly identifies the layer that anchors the vessel to surrounding tissues?

• A. Tunica Adventitia
• B. Tunica Media
• C. Tunica Intima
• D. Endothelium

Answer: (A)

Anchoring the vessel to surrounding tissues is the job of the outermost layer, the tunica adventitia. This layer is made of connective tissue rich in collagen (and some elastic fibers) that securely tethers the vessel to nearby structures and provides structural support. It also houses small vessels and nerves that supply the vessel wall (vasa vasorum) in larger vessels. The middle layer, tunica media, is primarily smooth muscle that controls vessel diameter and blood flow, not anchoring. The innermost layer, tunica intima, lines the lumen and consists of endothelial cells; endothelium is just the inner lining, not a tether to surrounding tissues. So the description fits the adventitia.

Anchoring the vessel to surrounding tissues is the job of the outermost layer, the tunica adventitia. This layer is made of connective tissue rich in collagen (and some elastic fibers) that securely tethers the vessel to nearby structures and provides structural support. It also houses small vessels and nerves that supply the vessel wall (vasa vasorum) in larger vessels. The middle layer, tunica media, is primarily smooth muscle that controls vessel diameter and blood flow, not anchoring. The innermost layer, tunica intima, lines the lumen and consists of endothelial cells; endothelium is just the inner lining, not a tether to surrounding tissues. So the description fits the adventitia.