Make the following morphological comparisons between the artery and vein.
1. The artery (A) has a thicker wall than the vein (V).
2. The lumen surface of the artery is undulating, compared to the smooth surface of the vein.
3. The lumen diameter of the artery is smaller than that of the vein.
4. The artery has a more distinctive layering of the vessel wall than the vein.
