Podcast
Questions and Answers
Which of the following is NOT a major component of the circulatory system?
Which of the following is NOT a major component of the circulatory system?
What is the purpose of having separate atrial and ventricular syncytia in the heart?
What is the purpose of having separate atrial and ventricular syncytia in the heart?
Which of the following is the only normal electrical pathway between the atria and the ventricles?
Which of the following is the only normal electrical pathway between the atria and the ventricles?
Which ion primarily determines the resting membrane potential?
Which ion primarily determines the resting membrane potential?
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Which channel is responsible for hyperpolarization-activated cyclic nucleotide-gated channel?
Which channel is responsible for hyperpolarization-activated cyclic nucleotide-gated channel?
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What is the role of the SA node in the heart?
What is the role of the SA node in the heart?
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What is the mechanism that suppresses latent pacemakers from driving the heart rate?
What is the mechanism that suppresses latent pacemakers from driving the heart rate?
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Which component of the circulatory system carries oxygenated blood away from the heart to tissues?
Which component of the circulatory system carries oxygenated blood away from the heart to tissues?
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What is the primary function of the cardiovascular system?
What is the primary function of the cardiovascular system?
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What is the total flow of blood out of the left ventricle known as?
What is the total flow of blood out of the left ventricle known as?
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Which type of cardiac muscle cells do not contribute to the generation of force for pumping blood?
Which type of cardiac muscle cells do not contribute to the generation of force for pumping blood?
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Which type of current is responsible for repolarization in phase 3 of the action potential?
Which type of current is responsible for repolarization in phase 3 of the action potential?
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What is the main effect of sympathetic nerves on heart rate?
What is the main effect of sympathetic nerves on heart rate?
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What is the effect of parasympathetic nerves on heart rate?
What is the effect of parasympathetic nerves on heart rate?
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During which phase of the action potential are most Na+ channels closed?
During which phase of the action potential are most Na+ channels closed?
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Which part of the heart has the fastest conduction velocity?
Which part of the heart has the fastest conduction velocity?
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Which part of the heart has the slowest conduction velocity?
Which part of the heart has the slowest conduction velocity?
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What is the purpose of the slow conduction velocity in the AV node?
What is the purpose of the slow conduction velocity in the AV node?
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What is the purpose of the rapid conduction velocity in the Purkinje fibers?
What is the purpose of the rapid conduction velocity in the Purkinje fibers?
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Which receptor is coupled to GK that inhibits adenylyl cyclase?
Which receptor is coupled to GK that inhibits adenylyl cyclase?
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What effect does parasympathetic nerve activation have on heart rate?
What effect does parasympathetic nerve activation have on heart rate?
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What causes the negative shift in the maximum diastolic potential in SA nodal cells during parasympathetic nerve activation?
What causes the negative shift in the maximum diastolic potential in SA nodal cells during parasympathetic nerve activation?
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What does the PR interval on an ECG represent?
What does the PR interval on an ECG represent?
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Which receptor is coupled to GK that inhibits adenylyl cyclase?
Which receptor is coupled to GK that inhibits adenylyl cyclase?
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What effect does parasympathetic nerve activation have on heart rate?
What effect does parasympathetic nerve activation have on heart rate?
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What is the effect of sympathetic nervous system on conduction velocity through the AV node?
What is the effect of sympathetic nervous system on conduction velocity through the AV node?
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What does the PR interval on an ECG represent?
What does the PR interval on an ECG represent?
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Which ion is responsible for the upstroke of the action potential in SA cells?
Which ion is responsible for the upstroke of the action potential in SA cells?
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What is the role of HCN channels in the SA node?
What is the role of HCN channels in the SA node?
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What is the mechanism that suppresses latent pacemakers from driving the heart rate called?
What is the mechanism that suppresses latent pacemakers from driving the heart rate called?
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Which part of the heart is responsible for generating action potentials spontaneously?
Which part of the heart is responsible for generating action potentials spontaneously?
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What is the main function of conducting cells in the heart?
What is the main function of conducting cells in the heart?
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Which syncytium in the heart works as a coordinated unit to pump blood?
Which syncytium in the heart works as a coordinated unit to pump blood?
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What is the purpose of the AV node in the heart?
What is the purpose of the AV node in the heart?
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During which phase of the action potential are most Na+ channels closed?
During which phase of the action potential are most Na+ channels closed?
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What is the effect of sympathetic nerves on heart rate?
What is the effect of sympathetic nerves on heart rate?
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What is the effect of parasympathetic nerves on heart rate?
What is the effect of parasympathetic nerves on heart rate?
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Which receptor is coupled to GK that inhibits adenylyl cyclase?
Which receptor is coupled to GK that inhibits adenylyl cyclase?
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Which part of the heart has the slowest conduction velocity?
Which part of the heart has the slowest conduction velocity?
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What is the purpose of the slow conduction velocity in the AV node?
What is the purpose of the slow conduction velocity in the AV node?
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What is the purpose of having separate atrial and ventricular syncytia in the heart?
What is the purpose of having separate atrial and ventricular syncytia in the heart?
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What is the effect of sympathetic nervous system on conduction velocity through the AV node?
What is the effect of sympathetic nervous system on conduction velocity through the AV node?
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Which of the following is true about M2 receptors?
Which of the following is true about M2 receptors?
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What effect does sympathetic nervous system have on conduction velocity through the AV node?
What effect does sympathetic nervous system have on conduction velocity through the AV node?
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What does the QT interval on an ECG represent?
What does the QT interval on an ECG represent?
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Which of the following is NOT a cause of sinus tachycardia?
Which of the following is NOT a cause of sinus tachycardia?
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Which of the following is the correct sequence of cardiac activation (depolarization) starting from the SA node?
Which of the following is the correct sequence of cardiac activation (depolarization) starting from the SA node?
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Which of the following is responsible for lengthening the absolute refractory period in contractile cell action potentials?
Which of the following is responsible for lengthening the absolute refractory period in contractile cell action potentials?
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What are the major features of an ECG and what do they correspond to in the heart?
What are the major features of an ECG and what do they correspond to in the heart?
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Which of the following is responsible for the upstroke of the action potential in contractile cells?
Which of the following is responsible for the upstroke of the action potential in contractile cells?
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Which of the following best describes the role of the AV node in the heart?
Which of the following best describes the role of the AV node in the heart?
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Which of the following is NOT a major component of the circulatory system?
Which of the following is NOT a major component of the circulatory system?
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Which phase of the action potential is characterized by repolarization?
Which phase of the action potential is characterized by repolarization?
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What is the effect of sympathetic nervous system on heart rate?
What is the effect of sympathetic nervous system on heart rate?
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Which ion primarily determines the resting membrane potential?
Which ion primarily determines the resting membrane potential?
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What is the role of HCN channels in the SA node?
What is the role of HCN channels in the SA node?
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Which of the following is responsible for generating action potentials spontaneously in the heart?
Which of the following is responsible for generating action potentials spontaneously in the heart?
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Which part of the heart has the fastest conduction velocity?
Which part of the heart has the fastest conduction velocity?
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What is the main function of the conducting cells in the heart?
What is the main function of the conducting cells in the heart?
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What is the effect of parasympathetic nerve activation on heart rate?
What is the effect of parasympathetic nerve activation on heart rate?
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Which ion primarily determines the resting membrane potential?
Which ion primarily determines the resting membrane potential?
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What is the purpose of the slow conduction velocity in the AV node?
What is the purpose of the slow conduction velocity in the AV node?
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What is the effect of parasympathetic nerves on heart rate?
What is the effect of parasympathetic nerves on heart rate?
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What is the role of HCN channels in the SA node?
What is the role of HCN channels in the SA node?
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Which part of the specialized conduction system has the fastest conduction velocity?
Which part of the specialized conduction system has the fastest conduction velocity?
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What is the purpose of the slow conduction velocity in the AV node?
What is the purpose of the slow conduction velocity in the AV node?
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What is the main function of the specialized conduction system in the heart?
What is the main function of the specialized conduction system in the heart?
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What is the effect of sympathetic nervous system on conduction velocity through the AV node?
What is the effect of sympathetic nervous system on conduction velocity through the AV node?
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Which of the following is true about M2 receptors?
Which of the following is true about M2 receptors?
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What does the PR interval on an ECG represent?
What does the PR interval on an ECG represent?
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What effect does parasympathetic nerve activation have on heart rate?
What effect does parasympathetic nerve activation have on heart rate?
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What is the purpose of the slow conduction velocity in the AV node?
What is the purpose of the slow conduction velocity in the AV node?
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