Which vessel layer is the innermost, containing endothelial cells and connective tissue?

Which vessel layer is the innermost, containing endothelial cells and connective tissue?

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

Answer: (A)

The innermost vessel layer is the tunica intima. It sits directly in contact with blood and is made up of endothelial cells lining the lumen plus a subendothelial connective tissue layer. So while the endothelial lining is a key component, the full inner layer name that includes both the endothelium and the connective tissue is tunica intima. The middle layer is the tunica media, rich in smooth muscle, and the outer layer is the tunica adventitia, which is connective tissue that anchors the vessel.

The innermost vessel layer is the tunica intima. It sits directly in contact with blood and is made up of endothelial cells lining the lumen plus a subendothelial connective tissue layer. So while the endothelial lining is a key component, the full inner layer name that includes both the endothelium and the connective tissue is tunica intima. The middle layer is the tunica media, rich in smooth muscle, and the outer layer is the tunica adventitia, which is connective tissue that anchors the vessel.