Which are lined with muscle tissue, veins or arteries?
Arterial wall is associated with a thick layer of smooth muscles.
Wall of blood vessel has three concentric layers:
- Tunica interna- squamous epithelial lining
Tunica media- smooth muscle fibres and elastin
Tunica externa- adventitia of collagen
Tunica media is highly thickened in wall of arteries. This is because arterial walls are exposed to high blood pressure due to pumping action of heart.