BSC 216 Heart A&P HW
Place the following parts of the cardiac conduction system in the order in which they transmit the action potential. 1. atrioventricular (AV) bundle 2. Purkinje fibers 3. sinoatrial (SA) node 4. right and left bundle branches 5. contractile cells of cardiac muscle tissue 6. atrioventricular (AV) node
3, 6, 1, 4, 2, 5
The right side of the heart pumps deoxygenated blood into __________.
B pulmonary arteries
What action causes the first heart sound heard through a stethoscope?
Closing of the atrioventricular valves
Which part of the electrocardiogram (ECG) would most be affected by abnormally slow depolarization of the ventricles?
QRS complex
Which wave on the electrocardiogram (ECG) represents ventricular depolarization?
QRS complex
Which of the following can be used to measure heart rate?
R-R interval
The main pacemaker of the heart is the __________.
SA node
Which of the following happens immediately after the P wave?
The atria contract
Determine the impact if the connection between the sinoatrial (SA) node and the atrioventricular (AV) node becomes blocked.
The ventricles will contract more slowly
Pressure in the aorta is greater than pressure in the pulmonary trunk; therefore, the left ventricle has to generate a greater pressure than the right ventricle in order to eject blood from the heart. (T/F)
True
The right and left coronary arteries receive blood from the:
aorta
What vessel delivers oxygenated blood to systemic capillaries for gas exchange?
aorta
Where should the left ventricle send blood?
aorta
Which vessel supplies the systemic circuit with oxygenated blood?
aorta
The P wave on an electrocardiogram (ECG) represents the depolarization of cells in the:
atria
What is NOT part of the cardiac conduction system?
atrioventricular (AV) valve
The electrical impulse is __________ as it passes through the AV node, which permits the atria to contract __________ ventricles.
delayed; before
The right side of the heart receives:
deoxygenated blood from the systemic circuit
The apex of the heart is __________.
inferior
As ventricular systole begins, all four heart valves are closed during the:
isovolumetric contraction phase.
Blood returning from the lungs enters the __________.
left atrium
Which heart chamber receives blood from the pulmonary veins?
left atrium
Which chamber pumps oxygenated blood out the aorta to the systemic circuit?
left ventricle
The pulmonary circuit involves blood flow from the heart to the:
lungs
The heart is situated in the middle of the thoracic cavity in a region known as the:
mediastinum
The cells that rhythmically and spontaneously generate action potentials in the heart are called __________.
pacemaker cells
What muscles, present in the ventricles, anchor the atrioventricular valves by tendon-like chords called chordae tendineae?
papillary muscles
The aortic valve closes when __________.
pressure in the left ventricle falls below aortic pressure
The AV valves close when __________.
pressure in the ventricles increases
What is the function of the valves in the heart?
prevent backflow of blood through the heart
Blood that leaves the right ventricle enters the __________.
pulmonary trunk
Which vessel is guarded by a semilunar valve at its base?
pulmonary trunk
Which of the following does NOT return blood to the right atrium of the heart?
pulmonary vein
Blood in the right ventricle arrived from the:
right atrium
Which chamber receives blood from the superior and inferior vena cavae?
right atrium
Which heart chamber pumps unoxygenated blood out the pulmonary trunk?
right ventricle
What normally serves as the pacemaker of the entire heart?
sinoatrial (SA) node
The right and left atria depolarize and contract following the arrival of the action potential from the:
sinoatrial (SA) node.
The vessels that deliver oxygen to the tissues of the body are part of the __________.
systemic circuit
As a result of the long refractory period in the contractile cell, cardiac muscle can NOT exhibit:
tetany
What valve prevents the backflow of blood from the right ventricle into the right atrium?
tricuspid valve
The left side of the heart is often called the systemic pump due to blood flow to the body. (T/F)
true
The left ventricle has greater muscle mass than the right ventricle since it pumps against greater resistance. (T/F)
true
The heart is actually (one, two, or three) pumps?
two pumps
Both the left and right atria receive blood from:
veins
Blood from the systemic circuit returns to the heart via the __________.
venae cavae
The chambers that have just emptied when the second heart sound is heard are the __________.
ventricles
During what phase does blood flow from the ventricles into the pulmonary trunk and aorta?
ventricular ejection phase
The T wave of an ECG corresponds to __________.
ventricular repolarization
