Structure of a Vein Wall Diagram

The Structure of a Vein Wall diagram layers out the typical three-part construction: a thin tunica intima with endothelium for smooth flow, a thicker tunica media with some smooth muscle and collagen for support, and the outermost tunica adventitia rich in connective tissue and vasa vasorum. Valves are often shown in larger veins to prevent backflow. This basic cross-section helps explain why veins are more collapsible than arteries and their role in returning blood under lower pressure.