Blood vessels

• Arteries:

  • Carry blood away from heart.
  • High blood pressure.
  • Strong and elastic.
  • Thick walls.
• Veins:

  • Carry blood to heart.
  • Cappilaries joing up to make veins.
  • Low blood pressure.
  • Big lumen to help blood flow.
  • Valves to keep blood from backflow.
• Cappilaries :

  • Join arteries and veins.
  • Carry blood close to cells to exchange substances.
  • Supply food and oxygen, take waste co2.
  • Thin walls for diffusion