Heart Quiz

Which network of specialized cardiac muscle fibers provide a path for each cycle of cardiac excitation to progress through the heart?

Cardiac conduction system

Blood flows through the right coronary artery (RCA) to the anterior interventricular and circumflex branches.

False

Blood, or any other liquid, flows from an area of low pressure to an area of high pressure.

False

The purpose of the chordae tendinae is to open and close the atrioventricular valves.

False

The right ventricle has a thicker wall than the left ventricle, because of its heavier work load.

False

Which of the following describe the relaxation period of the cardiac cycle?

It is a time that becomes shorter as the heart rate increases.

Which of the following correctly lists the sequence of structures that a cardiac action potential follows in order to excite normal contraction of the heart?

SA node, AV node, Bundle of His, Purkinje fibers

The second heart sound (dupp) closely follows which of the events listed below?

Semilunar valves closing

Represents time when ventricles are repolarizing

T wave

Why doesn't a significant amount of blood flow back into the vena cavae and coronary sinus during atrial contraction?

the contraction of the atria compresses and closes the venous openings

The right coronary artery does NOT supply blood to

the left atrium

Why is the myocardium of the left ventricle thicker than the myocardium of the right ventricle?

the left ventricle has to overcome a greater peripheral resistance

Isovolumetric contraction is the phase of the cardiac cardiac cycle in which

ventricular pressure increases and ventricular volume remains the same.

Put the following structures in the correct order of blood flow, starting with venous blood entering the heart through the superior and inferior vena cavae.

1 right atrium 2 right ventricle 3 pulmonary trunk and arteries 4 pulmonary capillaries 5 pulmonary veins 6 left atrium 7 left ventricle 8 aorta and systemic arteries

The only site where action potentials conduct from the atria to the ventricles is the

AV bundle (Bundle of His)

Arteries always conduct blood away from the heart, while veins conduct blood towards the heart.

True

Because the output of one blood flow circuit becomes the input of the other, the two sides of the heart contract simultaneously and eject the same volume of blood.

True

Cardiac tamponade results from accumulation of fluid within the pericardial cavity

True

Compression of the endomyocardial arteries during ventricular contraction causes blood to flow through the coronary circulation ONLY during ventricular relaxation.

True

The heart chambers must be filled before contracting, so correct timing (atria followed by ventricles) is critical for efficient pumping.

True

The serous pericardium is divided into an outer parietal layer and an inner visceral layer, which is adhered to the surface of the heart.

True

In comparison to a sedentary individual, a well-trained athlete will usually have all the following characteristics EXCEPT

a higher resting cardiac output.

Which of the following is FALSE?

b. The plateau period in contractile myocardial cells results from the entry of K+ into the cells

The left atrioventricular valve is also known as the ___________ valve.

bicuspid

Which of the following is TRUE?

c. The intrinsic rate of depolarization of the SA node can be modified by the autonomic nervous system

Choose the CORRECT statement.

c. The right atrium receives deoxygenated blood from the venous circulation

The amount of blood contained in a ventricle at the end of atrial systole is the

end-diastolic volume

Each of the cardiac valves

ensures one-way blood flow through the heart.

Cardiac muscle tissue is characterized by all of these EXCEPT:

multinucleated cells

Cardiac muscle cells

none of the above are true

Which of the structures below is held closed during ventricular diastole by back flow of blood coming from the lungs?

pulmonary SL valve

Which of the following is NOT a vessel entering the right atrium?

pulmonary vein

Waste filled blood from cardiac muscle itself enters the __________________ chamber of the heart through which vessel?

right atrium; coronary sinus