Blood vessels

• What is the primary function of the heart in the circulatory system?

  It acts as the system's pump
• What are the three types of blood vessels discussed?

  Arteries, capillaries, and veins
• What do arteries do with blood?

  Carry blood away from the heart
• What is the role of capillaries?

  Exchange nutrients and oxygen with tissues
• What do veins do with blood?

  Carry blood back to the heart
• How is the structure of arteries related to their function?

  They are strong and elastic to handle high pressure
• Why do arteries have thick walls?

  To withstand high blood pressure
• What is the lumen of a blood vessel?

  The hole or space in the middle
• How are capillaries adapted for their function?

  They have walls that are one cell thick
• What does it mean for capillaries to be permeable?

  Substances can easily diffuse through them
• Why is the total cross-sectional area of capillaries significant?

  It is much larger than that of arteries
• What happens to blood pressure as it moves from arteries to capillaries?

  It decreases significantly
• What are veins characterized by?

  Relatively large lumens and thin walls
• What do veins have to prevent backflow?

  Valves
• How do you calculate the rate of blood flow?

  Divide blood volume by time
• If 2500 ml of blood passes through the aorta in 8 minutes, what is the rate of blood flow?

  320 milliliters per minute
• What are the key functions of arteries, capillaries, and veins?

  • Arteries: Carry blood away from the heart
  • Capillaries: Exchange nutrients and oxygen with tissues
  • Veins: Return blood to the heart
• What are the structural differences between arteries, capillaries, and veins?

  • Arteries: Thick walls, strong, elastic
  • Capillaries: One cell thick, permeable
  • Veins: Thin walls, large lumens, valves present