Paper 3 structured question: Blood vessels
Paper 3Theory (Core)2 marks
Diagram Description
Diagram of blood vessels
A diagram shows three types of blood vessels: artery, vein, and capillary. The artery has a thick wall and narrow lumen, the vein has a thinner wall and wider lumen with valves, and the capillary has a very thin wall and very narrow lumen.
| Characteristic | Artery | Vein | Capillary |
|---|---|---|---|
| Wall thickness | Thick | Thin | One cell thick |
| Lumen size | Narrow | Wide | Very narrow |
| Valves present | No | Yes | No |
- a[2]
Describe the differences in wall thickness between arteries, veins, and capillaries.