Blood vessels

• What are the four types of blood vessels discussed?

  Arteries, arterioles, capillaries, veins
• What is the primary function of arteries?

  To carry blood away from the heart
• How do arterioles relate to arteries?

  Arterioles are smaller branches of arteries
• What do capillaries connect?

  Arterioles to veins
• What do veins carry back to the heart?

  Blood
• What is the significance of the lumen in blood vessels?

  It is the space for blood flow
• How does the lumen size of veins compare to arteries?

  Veins have a larger, irregular lumen
• Why are artery walls thicker than vein walls?

  To withstand higher blood pressure
• What are the three tissue types found in both arteries and veins?

  Muscular layer, elastic layer, valves
• What is the role of the muscular layer in arteries?

  To constrict and dilate for blood control
• Why do veins have valves?

  To prevent backflow of blood
• What is the thickness of the elastic layer in arteries compared to veins?

  Much thicker in arteries
• What happens to the elastic layer in veins?

  It is relatively thin
• What is the function of the capillary wall?

  To provide a short diffusion distance
• How thick is a capillary wall?

  One cell thick
• Why is slower blood flow advantageous in capillaries?

  It allows more time for diffusion
• Where are capillaries commonly found?

  In villi, alveoli, nephron
• What are the key differences between arteries and veins?

  • Arteries carry blood away from the heart
  • Veins carry blood back to the heart
  • Arteries have thicker walls than veins
  • Veins have valves to prevent backflow
• What are the characteristics of arterioles compared to arteries?

  • Arterioles connect arteries to capillaries
  • They have a thicker muscular layer than arteries
  • They help restrict blood flow to capillaries
  • They have a thinner elastic layer than arteries
• What is the structure and function of capillaries?

  • Capillaries are one cell thick
  • They allow for slow blood flow
  • They provide a short diffusion distance
  • They are found in networks called capillary beds