Blood Vessel Structure and Function

Which type of blood vessel has thick walls containing lots of elastic tissue ?

• Arterioles

• Capillaries

• Veins

• Arteries

What is the primary function of arteries in the circulatory system ?

• To regulate blood flow within organs

• To serve as pressure reservoirs

• To exchange gases and nutrients

• To drain deoxygenated blood back to the heart

During systole, blood is ejected into the arteries. This causes the arterial wall to:

• Recoil and push blood forward

• Stretch in response to the force

• Decrease in size

• Increase in elasticity

Which of the following accurately describes how arterial blood pressure is maintained ?

• The arterial walls recoil during diastole, pushing blood forward

• Blood pressure decreases to zero before the next systole

• Blood pressure is entirely maintained by the heart's contraction force

• Arteries contract to maintain constant pressure

What is "Pulse pressure" ?

• Pressure exerted by the blood on the vessel wall

• The difference between systolic pressure and diastolic pressure

• The average pressure in the arteries during one cardiac cycle

• The pressure measured during diastole

What causes an increase in pulse pressure with age ?

• Increased blood volume

• Increased elasticity of the arteries

• Decreased elasticity of the arteries (arteriosclerosis)

• Increased heart rate

What does mean arterial pressure (MAP) depend on?

• Cardiac output and total resistance

• The viscosity of the blood

• The volume of blood in the system

• The size of the arteries

Why is total resistance (TR) higher in the systemic circuit than in the pulmonary circuit ?

• There are more blood vessels in the systemic circuit

• The pulmonary circuit has larger arteries

• The systemic circuit is shorter than the pulmonary circuit

• Blood flow is restricted in the pulmonary cicuit

What is the main factor that determines the resistance in a blood vessel ?

• The length of the vessel

• The viscosity of the blood

• The radius of the vessel

• The cardiac outptu

What happens when the smooth muscle in the arterioles contracts ?

• Vasodilation occurs, and resistance decreases

• Vasoconstriction occurs, and resistance increases

• The vessel radius increases, and resistance decreases

• The vessel wall stretches and blood pressure drops