Questions and Answers
Which heart chamber sends deoxygenated blood to the lungs?
right ventricle
The heart is actually how many pumps?
Which chamber receives blood from the superior and inferior vena cavae?
right atrium
Which heart chamber receives blood from the pulmonary veins?
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Which heart chamber pumps unoxygenated blood out the pulmonary trunk?
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Which chamber pumps oxygenated blood out the aorta to the systemic circuit?
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Which of the following is NOT a difference between the left and right ventricles?
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The heart's pacemaker is the?
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Which term refers to a lack of oxygen supply to heart muscle cells?
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Which part of the conduction system initiates the depolarizing impulse?
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What does the ECG wave tracing represent?
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What does the QRS complex represent in the ECG wave tracing?
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Contraction of the atria results from which wave of depolarization on the ECG tracing?
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Which part of the intrinsic conduction system delays the impulse briefly?
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Which of the following would increase cardiac output to the greatest extent?
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Which of the following would increase heart rate?
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How would an increase in the sympathetic nervous system increase stroke volume?
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By what mechanism would an increase in venous return increase stroke volume?
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How would a decrease in blood volume affect both stroke volume and cardiac output?
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The QRS complex represents __________.
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What does the T wave of the electrocardiogram (ECG) represent?
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The left ventricular wall of the heart is thicker than the right wall in order to ________.
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Blood within the pulmonary veins returns to the ______.
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Which of the following is the outermost covering of the heart?
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Which layer of the heart wall contracts and is composed primarily of cardiac muscle tissue?
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Which of the following does NOT deliver blood to the right atrium?
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The __________ valve is located between the right atrium and the right ventricle.
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Which of the events below does not occur when the semilunar valves are open?
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What structures connect the individual heart muscle cells?
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At what rate does the sinoatrial (SA) node ensure depolarization in the heart?
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Specifically, what part of the intrinsic conduction system stimulates the atrioventricular (AV) node?
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Which portion of the electrocardiogram represents the time during which the atria repolarize?
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During which portion of the electrocardiogram do the atria contract?
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Which of the following increases stroke volume?
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The first heart sound (the "lub" of the "lub-dup") is caused by __________.
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Which of the following would increase heart rate?
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Which of the following is NOT a factor that regulates stroke volume?
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Normal heart sounds are caused by which of the following events?
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Hemorrhage with a large loss of blood causes ______.
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Which of the following factors does not influence heart rate?
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A foramen ovale ______.
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Autonomic regulation of heart rate is via two reflex centers found in the pons.
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As pressure in the aorta rises due to atherosclerosis, more ventricular pressure is required to open the aortic valve.
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Study Notes
Heart Anatomy and Function
- The right ventricle sends deoxygenated blood to the lungs through the pulmonary trunk.
- The heart operates as two pumps: one for the pulmonary circuit (right side) and one for the systemic circuit (left side).
- The right atrium receives unoxygenated blood from the superior and inferior vena cavae.
- Oxygenated blood from the pulmonary veins returns to the left atrium.
- The left ventricle pumps oxygenated blood into the aorta for systemic distribution.
Heart Chambers and Valves
- The right ventricle is responsible for pumping unoxygenated blood out to the pulmonary trunk.
- The left ventricle, characterized by thicker walls, pumps blood with greater pressure into the systemic circuit.
- The tricuspid valve is located between the right atrium and right ventricle, regulating blood flow.
- The fibrous pericardium serves as the outermost covering of the heart.
Conduction System and Pacemaker
- The sinoatrial (SA) node located in the right atrial wall functions as the heart's pacemaker.
- Electrical signals from the SA node initiate depolarization and spread throughout the heart.
- The atrioventricular (AV) node temporarily delays impulses to allow for effective atrial contraction before ventricular contraction.
- Intercalated discs connect individual heart muscle cells, facilitating coordinated contractions.
Electrocardiogram (ECG) Waves and Functions
- ECG wave tracing reflects the electrical activity of the heart, including depolarization and repolarization.
- The P wave indicates atrial depolarization leading to atrial contraction.
- The QRS complex signifies ventricular depolarization, with greater mass leading to a distinct wave.
- The T wave represents ventricular repolarization as the heart prepares for its next contraction.
Cardiac Output and Heart Rate Regulation
- Cardiac output is determined by heart rate multiplied by stroke volume.
- An increase in venous return raises stroke volume by enhancing end-diastolic volume due to the Frank-Starling mechanism.
- Factors increasing stroke volume include exercise and enhanced contractility via the sympathetic nervous system.
- The release of epinephrine and norepinephrine boosts heart rate during sympathetic stimulation.
Pathological Conditions and Responses
- Ischemia refers to inadequate oxygen supply to heart muscle cells, potentially leading to damage.
- Hemorrhage can lead to lowered blood pressure as a result of altered cardiac output.
- Autonomic regulation of heart rate involves reflex centers primarily found in the brainstem, not just the pons.
Fetal Heart Considerations
- The foramen ovale connects the two atria in the fetal heart, allowing blood to bypass the lungs prior to birth.
Studying That Suits You
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Description
Test your knowledge with these flashcards from Anatomy & Physiology II, Chapter 18. This chapter focuses on the heart's structure and functions, including how blood is circulated through the body and lungs. Perfect for reviewing key concepts and terminology.
