Describe the cardiac cycle and explain what drives it.
a. The heart contracts to pump blood through the body during systole and is filled with blood during diastole. An electrical charge spontaneously pulses from SA node causing two atria to contract. The pulse reaches AV node where it pauses before spreading to the walls of the ventricles. It enters the bundle of His, then to left and right bundle branches extending through the interventricular septum. Purkinje fibers conduct impulse from the apex up the ventricular myocardium, causing the ventricles to contract. This pause allows the atria to empty their contents into the ventricles before the ventricles pump out the blood.
b. The heart contracts to pump blood through the body during diastole and is filled with blood during systole. An electrical charge spontaneously pulses from SA node causing two atria to contract. The pulse reaches AV node where it pauses before spreading to the walls of the ventricles. It enters the bundle of His, then to left and right bundle branches extending through the interventricular septum. Purkinje fibers conduct the impulse from the apex up the ventricular myocardium, causing the ventricles to contract. This pause allows the atria to empty their contents into the ventricles before the ventricles pump out the blood.
c. The heart contracts to pump blood through the body during systole and is filled with blood
during diastole. An electrical charge spontaneously pulses from AV node causing two atria to contract. The pulse reaches SA node where it pauses before spreading to the walls of the ventricles. It enters the bundle of His, then to left and right bundle branches extending through the interventricular septum. Purkinje fibers conduct impulse from the apex up the
ventricular myocardium, causing the ventricles to contract. This pause allows the atria to empty their contents into the ventricles before the ventricles pump out the blood.
d. The heart contracts to pump blood through the body during systole and is filled with blood during diastole. An electrical charge spontaneously pulses from SA node causing two atria to contract. The pulse reaches AV node where it pauses before spreading to the walls of the ventricles. It enters the Purkinje fibers, then to left and right bundle branches extending through the interventricular septum. The bundle of His conduct impulse from the apex up the ventricular myocardium, causing the ventricles to contract. This pause allows the atria to empty their contents into the ventricles before the ventricles pump out the blood.