The Heart, Cardiac Cycle and Coordination

What does diastole mean in the context of the cardiac cycle?

• Decrease in heart rate

• Increase in blood pressure

• Relaxation of the heart

• Contraction of the heart

What is systole?

• Relaxation of the heart chambers

• Contraction of the heart chambers

• Stabilization of heart rate

• Decrease in blood pressure

Why would the whole heart not undergo systole at the same time?

• It would decrease heart rate

• It would stop blood flow

• It would increase blood pressure

• It would cause a heart attack

What does the atrial pressure graph represent?

• Blood pressure in the pulmonary artery

• Blood pressure in the atria

• Blood pressure in the aorta

• Blood pressure in the ventricles

Why can ventricular pressure go much higher than atrial pressure?

• Because the ventricles have a larger volume

• Because of the thinner walls of the ventricles

• Because of the thicker walls of the ventricles

• Because the atria contract more strongly

What does the aortic pressure graph indicate?

• Blood pressure in the aorta

• Blood pressure in the pulmonary artery

• Blood pressure in the ventricles

• Blood pressure in the atria

How long does one cardiac cycle last?

• 0.9 to 1.0 seconds

• 0.7 to 0.8 seconds

• 0.5 to 0.6 seconds

• 1 to 1.2 seconds

What happens during atrial systole?

• The ventricles relax

• The atria contract

• The atria relax

• The ventricles contract

What is the significance of ventricular diastole?

• The atria relax

• The ventricles contract

• The atria contract

• The ventricles relax

What triggers the opening of the semilunar valves?

• Atrial pressure being higher than ventricular pressure

• Ventricular pressure being higher than aortic pressure

• Aortic pressure being higher than ventricular pressure

• Ventricular pressure being lower than atrial pressure