Exam 7: Cardiac Physiology

An increase in heart rate ____________________ the cardiac output.

Parasympathetic stimulation of the AV node increases the speed of transmission of the impulse through the AV node.

If the EDV were held constant,what could accomplish increased stroke volume?

What is cardiac output?

An increase in parasympathetic activity ____________________ the heart rate.

When does blood flow occur through the coronary circulation?

The plateau of the cardiac action potential results from the opening of voltage-gated slow ______ channels in the plasma membrane of the cardiac cell.

When does electrical activity occur at the AV node?

Gap junctions are absent between atrial and ventricular cells.

Match heart characteristic with correct anatomical structure by using the answer code (options may be used more than once or not at all): -its closing partially creates the heart sound "lub"

The heart muscle receives its oxygen and nutrients directly from the blood within its chambers during ventricular diastole.

Indicate the effects of sympathetic and parasympathetic stimulation on the heart by using the answer code (options may be used more than once or not at all): -decreases the rate of depolarization to threshold of the SA node

What does extrasystole of the heart mean?

Indicate which factor involved in the initiation and spread of cardiac excitation is being identified by using the answer code (options may be used more than once or not at all): -the only point of electrical contact between the atria and ventricles

Match heart characteristic with correct anatomical structure by using the answer code (options may be used more than once or not at all): -electrically connects the atria to the ventricles

Which of the following are compensatory mechanisms that come into play in order to maintain the cardiac output for the failing heart?

Which of the following is correct for the first heart sound?

Diastole refers to the period of cardiac relaxation.

Complete the following statements by using the answer code (options may be used more than once or not at all): -The minimum volume of blood that the ventricle contains after emptying is complete is the _____.

The EDV of the heart averages about 65 mL.