Cardiac Cycle and Heart

Front

What phase of the cardiac cycle are the semilunar valves open?

Back

Ventricular ejection.

Front

What happens to the atrioventricular and semilunar valves during ventricular diastole?

Back

Atrioventricular valves open, semilunar valves close.

Front

Define ventricular systole.

Back

The phase of the cardiac cycle when the ventricles contract to pump blood out of the heart.

Front

Which chamber of the heart pumps deoxygenated blood to the lungs?

Back

Right Ventricle.

Front

What causes pressure changes in the ventricles during the cardiac cycle?

Back

Contraction and relaxation of muscles in ventricles.

Front

What is the role of the atrioventricular valves?

Back

To prevent backflow of blood from the ventricles into the atria during ventricular contraction.

Front

What occurs during isovolumetric contraction?

Back

The ventricles contract with no change in volume as all valves are closed.

Front

What is the function of the semilunar valves?

Back

To prevent backflow of blood from the arteries into the ventricles after contraction.

Front

Describe the cardiac cycle.

Back

The sequence of events in one heartbeat, including contraction and relaxation of the heart chambers.

Front

What is the significance of the 'lub-dub' sound in the heart?

Back

The 'lub' sound is caused by the closing of the atrioventricular valves, and the 'dub' sound is caused by the closing of the semilunar valves.