Week 9 - Quiz

Question 1

Which alteration would reduce venous return to the heart and therefore reduce end-diastolic volume?

a. Increasing rate or depth of breathing.
b. Increasing sympathetic signals to peripheral blood vessels.
c. Increasing skeletal muscle activity.
d. Increasing urine volume.
e. Increasing venoconstriction.

Answer 1

d. Increasing urine volume.

Question 2

Which value corresponds to the amount of pressure in the arteries that ventricles must overcome to push blood out of the ventricle?

a. Cardiac output.
b. Preload.
c. Afterload.
d. Stroke volume.

Answer 2

c. Afterload.

Question 2

Calculate the cardiac output for a patient whose heart beats 85 times in a minute and has a stroke volume 60 milliliters per beat.

a. 51 L/min.
b. 145 ml/min.
c. 85 ml/min.
d. 1.42 ml/min.
e. 5,100 ml/min.

Answer 2

e. 5,100 ml/min.

Question 3

How do we create negative intrathoracic pressure?

a. Urinating.
b. Wearing compression stockings (pushing fluid out of the lower limbs)
c. Moving our legs.
d. Venoconstriction.
e. Breathing.

Answer 3

e. Breathing.

Question 4

What is the strongest chamber of the heart?

a. Right ventricle.
b. Left ventricle.
c. Right atrium.
d. Left atrium.

Answer 4

b. Left ventricle.

Question 5

If afterload increases in the cardiovascular system what will happen to end-systolic volume?

a. ESV decreases.
b. ESV increases.

Answer 5

b. ESV increases.

Question 6

Which alteration would reduce preload?

a. Increasing venoconstriction.
b. Increasing physical activity.
c. Suffering from edema (build of fluid in tissues, swelling).
d. Increasing the rate ventilation.
e. Becoming angry and having blood pressure increase.

Answer 6

c. Suffering from edema (build of fluid in tissues, swelling).

Question 7

As an average person moves from resting conditions to intense exercise how much can their cardiac output increase at the higher end of
the spectrum?

a. It can quadruple.
b. It can triple.
c. It can double.

Answer 7

a. It can quadruple.

Question 8

At what sarcomere length (all are within normal ranges of what occurs in adults) will the ventricles be able to produce greatest contractile
force?

a. 2.2 micrometers.
b. 1.5 micrometers.
c. 2.4 micrometers.
d. 2.0 micrometers.

Answer 8

c. 2.4 micrometers.

Question 9

What description best fits the term end-diastolic volume?

a. The amount of blood in the ventricle just before the heart contracts.
b. The amount of blood remaining in the ventricle after the heart pumps.

Answer 9

a. The amount of blood in the ventricle just before the heart contracts.

Question 10

What description best fits the term end-systolic volume?

a. The amount of blood remaining in the ventricle after the heart pumps.
b. The amount of blood in the ventricle just before the heart contracts.

Answer 10

a. The amount of blood remaining in the ventricle after the heart pumps.

Question 11

If afterload and preload were exactly equal what would happen to blood flow through the heart.

a. Blood would be ejected (pumped) out of the ventricle.
b. No blood would flow into or out of the ventricles.
c. Blood would be pushed back into the ventricle from the arteries.

Answer 11

b. No blood would flow into or out of the ventricles.

Question 12

The dicrotic notch in the pressure graph of the aorta corresponds to what point in the cardiac cycle?

a. Ventricular ejection phase.
b. Ventricular filling.
c. Isovolumetric contraction phase.
d. Closure of the aortic valve.
e. Atrial contraction.

Answer 12

d. Closure of the aortic valve.

Question 13

If you subtract end-systolic volume from end-diastolic volume, what value have you calculated?

a. Stroke volume.
b. Heart rate.
c. Dicrotic notch.
d. Cardiac output.

Answer 13

a. Stroke volume.

Question 14

To ensure blood flow continues in the correct direction what region must have a lower blood pressure than the vena cava?

a. Right ventricle during systole.
b. Aorta.
c. Hepatic arteries (serving the liver).
d. Left ventricle during systole.
e. Right atrium during diastole.

Answer 14

e. Right atrium during diastole.

Question 15

What influence does sympathetic nervous system input have on the heart’s ability to create cardiac output?

a. Sympathetic innervation increases heart rate.
b. All listed options are impacts of sympathetic innervation on the heart.
c. Sympathetic innervation increases contractility of the heart.
d. Sympathetic innervation increases stroke volume of the heart.

Answer 15

b. All listed options are impacts of sympathetic innervation on the heart.

Question 16

Which of the following factors best fits the concept of afterload? The 3rd set of cardiac output lecture slides has a good image to help
with this.

a. Mean arterial pressure (i.e., blood pressure)
b. Cardiac output.
c. parasympathetic innervation of heart muscle.
d. End-diastolic volume.
e. Contraction strength of the ventricles.

Answer 16

a. Mean arterial pressure (i.e., blood pressure)

Question 17

According to the Frank-Starling law of the heart when will the ventricles be able to produce greatest contractile force?

a. When the ventricles are empty.
b. When the ventricles are half full.
c. When the ventricles are full.
d. When the ventricles become overfilled.

Answer 17

c. When the ventricles are full.

Question 18

What term is used to describe the period when both valves (AV and semilunar) are closed but pressure in the ventricles is increasing?

a. Ventricular ejection phase.
b. Isovolumetric contraction phase.
c. Atrial contraction.
d. Ventricular filling.
e. Closure of the aortic valve.

Answer 18

b. Isovolumetric contraction phase.

Question 19

If heart rate is created by a balance of sympathetic and parasympathetic input, what should happen if all sympathetic nervous input is
removed?

a. The heart rate should slow.
b. The heart rate should increase.
c. The heart rate should stay the same.

Answer 19

a. The heart rate should slow.

Question 20

If afterload increases in the cardiovascular system what will happen to stroke volume?

a. SV decreases.
b. SV increases.

Answer 20

a. SV decreases.

Question 21

What is an average heart rate for an adult?

a. 110 beats/minute.
b. 45 beats/minute.
c. 95 beats/minute.
d. 75 beats/minute.
e. 55 beats/minute.

Answer 21

d. 75 beats/minute.

Question 22

What is the function of the coronary sinus?

a. To dump blood into the right ventricle.
b. To bring blood to the left ventricle.
c. To bring blood to the aorta.
d. To return blood to the right atrium from the heart tissue.
e. To bring blood to the heart tissue from the aorta.

Answer 22

d. To return blood to the right atrium from the heart tissue.

Question 23

Which value is created by the degree of filling of the heart (end-diastolic volume) leading to stretch prior to contraction of the ventricle?

a. Preload.
b. Cardiac output.
c. Afterload.
d. Stroke volume.

Answer 23

a. Preload.