Exam 20: The Heart

The function of an atrium is to

The two types of cardiac muscle cells involved in a normal heartbeat include specialized cells of the conducting system and ________ cells.

The first blood vessels to branch from the aorta are the ________ arteries.

The long plateau phase of the cardiac muscle action potential is due to

Most of the middle layer in the heart wall is composed of

Abnormally slow depolarization of the ventricles would most change the shape of the ________ in an ECG tracing.

Considering the left ventricle,why does isovolumetric ventricular contraction occur during ventricular systole?

Blood returning to the heart from the pulmonary circuit first enters the

________ is when the heart can't maintain adequate cardiac output.

If the pacemaker cells in the SA node become more permeable to potassium ions,the

Blood is supplied to the muscular wall of the left atrium by the

During the T wave of the electrocardiogram,the ventricles are

The ________ valve prevents backward flow into the left atrium.

In mitral valve prolapse,the cusps of the mitral valve are pushed into the

The ________ circuit carries blood from the aorta to the right ventricle.

An increase in the rate of action potentials from baroreceptors will trigger a reflex to

A faster-than-normal heart rate is called

During ventricular systole,the

The left ventricle pumps blood to the

In what order would excitation move through the conducting system of the heart? 1)Purkinje fibers 4.SA node 2)AV bundle 5.bundle branches 3)AV node