PQ 8.2 THE VASCULAR SYSTEM AND BLOOD FLOW

What is the main function of capillaries in the cardiovascular system?

• Carrying deoxygenated blood to the lungs

• Regulating blood distribution to the various tissues

• Exchanging gases and nutrients with the tissues

• Transporting blood away from the heart

Which type of blood vessels have very thick muscular walls and carry blood away from the heart?

• Arterioles

• Capillaries

• Arteries

• Venules

What is the main role of arteries in the cardiovascular system?

• Returning blood to the heart

• Exchanging gases and nutrients with the tissues

• Regulating blood distribution to the various tissues

• Carrying oxygenated blood away from the heart

What is the function of the skeletal muscle pump in the return of blood to the heart?

• Increasing the delivery of blood to the working muscle

• Regulating blood clotting

• Pushing or massaging blood back to the heart with each muscle contraction

• Assisting in the distribution of blood to different organs

Which component makes up about 55 percent of blood and is composed mostly of water?

• Plasma

• Red blood cells

• Platelets

• White blood cells

What is the main function of veins in the cardiovascular system?

• Regulating blood distribution to the various tissues

• Carrying oxygenated blood away from the heart

• Exchanging gases and nutrients with the tissues

• Returning blood to the heart for another trip throughout the vascular system

What is the role of the thoracic pump in the return of blood to the heart?

• Creating a difference in pressure between the veins in the chest and abdominal cavities

• Pushing or massaging blood back to the heart with each muscle contraction

• Regulating blood clotting

• Assisting in the distribution of blood to different organs

Which type of blood vessels are surrounded by rings of smooth muscle and can contract or relax to regulate blood flow?

What is the main role of the nervous system in the return of blood to the heart?

• Assisting in the distribution of blood to different organs

• Pushing or massaging blood back to the heart with each muscle contraction

• Causing veins to slightly constrict to return more blood to the heart

• Creating a difference in pressure between the veins in the chest and abdominal cavities

What is the function of autoregulation in the cardiovascular system?