Blood Vessels

• Arteries

  • Transport blood away from the heart.
  • Thick walls resist high pressure.
• Capillaries

  • Arterioles branch and become small capillaries.
  • Facilitates the exchange of substances between blood and cell.
  • Blood flow is slow to improve the effectiveness of gaseous exchange.
• Veins

  • Capillaries reunite and form venules and then form veins.
  • Veins transport blood to the heart.
  • Blood pressure is low due to larger lumen.