Blood Vessels, Part 1

What is NOT a function of blood vessels?

• Delivering oxygen and nutrients to cells

• Carrying waste products away from cells

• Pumping blood through the heart

• Maintaining blood pressure

Which layer of blood vessel tissue is in direct contact with blood?

• Endothelium

• Tunica media

• Tunica intima

• Tunica externa

What happens to your blood vessels when you are cold?

• They expand to release heat

• They contract to conserve heat

• They burst due to high pressure

• They remain unchanged

How do veins assist in returning blood to the heart?

• By expanding their diameter

• By increasing blood pressure

• By using venous valves

• By pumping blood actively

Approximately how much blood does your circulatory system move through your heart every day?

• 75 liters

• 750 liters

• 7,500 liters

• 750,000 liters