Function of the Heart

Question 1

The sequence of events occurring during one heartbeat.

Answer 1

Cardiac cycle

Question 2

A coordinated contraction and relaxation of the chambers of the heart.

Answer 2

Cardiac cycle

Question 3

Contraction of the heart muscle (myocardium).

Answer 3

Systole (sis-toh-lee)

Question 4

Contraction of the heart muscle pumps blood out of a chamber during ___.

Answer 4

systole

Question 5

Relaxation of the myocardium.

Answer 5

Diastole (dye-ass-toh-lee)

Question 6

Blood fills a chamber during ___.

Answer 6

diastole

Question 7

The atria contract and pump blood into the ventricles.

Answer 7

Atrial systole

Question 8

Atrial and ventricular muscle activity is closely coordinated. For example, during atrial systole, the ventricles are in ___. In this way, when the atria contract, they pump blood into the relaxed ventricles.

Answer 8

diastole

Question 9

At the end of atrial systole, the ventricles contract; this is called:

Answer 9

ventricular systole

Question 10

During ___ ___, the atrioventricular (AV) valves are open and the ventricles are relaxed.

Answer 10

atrial systole

Question 11

As ventricular contractions begin, blood is forced against the ___ valves, causing them to snap shut. The blood pushes the ___ valves open, allowing blood to flow into the pulmonary trunk and aorta.

Answer 11

AV / semilunar

Question 12

For a brief period during the cardiac cycle, both the atria and the ventricles are in ___.

Answer 12

diastole (dai-a-stuh-lee)

Question 13

As the chambers relax, blood flows into the atria. Because the AV valves are open during this period, much of this blood also flows passively into the ventricles. The period of diastole therefore is a period of ___ (of blood); atrial systole follows. The cycle then repeats itself.

Answer 13

filling

Question 14

The ___ stages of the cardiac cycle.

Answer 14

3