Structure and function of blood vessels

Which type of blood vessel transports blood away from the heart?

• Capillaries
• Veins
• Venules
• Arteries

Why do veins transport blood to the heart at low pressure?

• To increase blood flow rate
• To facilitate substance exchange
• To prevent backflow of blood
• To maintain blood pressure

What is the function of veins in the circulatory system?

• Carry blood to the cells
• Form capillary beds
• Transport blood to the heart
• Transport blood away from the heart

Which type of blood vessel has a narrow lumen and carries blood to the cells?

• Arteries
• Veins
• Capillaries
• Venules

What is the primary function of the endothelium in blood vessels?

• Reduce friction for free blood flow
• Allow substances to leave the blood to reach tissues
• Provide structural support to the vessel
• Enable expansion under high pressure

Why do arteries have a thick layer of elastic and muscle tissue?

• To allow for rapid blood flow
• To withstand high pressure
• To facilitate substance exchange
• To provide structural support

What is the purpose of valves in veins?

• Regulate blood pressure
• Prevent backflow of blood
• Control blood oxygen levels
• Increase blood flow rate

Why do capillaries have thin walls that are permeable?

• To provide structural support
• To allow for rapid blood flow
• To withstand high pressure
• To facilitate substance exchange

What is the significance of the narrow lumen in capillaries?

• To prevent substance exchange
• To increase blood pressure
• To force blood to travel slowly
• To allow for rapid blood flow

Which type of blood vessel has a single layer of endothelial cells in its wall?

• Venules
• Capillaries
• Veins
• Arteries