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Questions and Answers
What effect does marked hyperkalemia have on the heart?
What effect does marked hyperkalemia have on the heart?
What is the main purpose of using digitalis in heart failure treatment?
What is the main purpose of using digitalis in heart failure treatment?
What does end diastolic volume refer to?
What does end diastolic volume refer to?
Which term is used to describe the ability of cardiac muscle to convert electrical and chemical changes into mechanical work?
Which term is used to describe the ability of cardiac muscle to convert electrical and chemical changes into mechanical work?
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What is the effect of +ve inotropic activity on contractility?
What is the effect of +ve inotropic activity on contractility?
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What determines the initial length of the cardiac muscle?
What determines the initial length of the cardiac muscle?
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What is the volume of blood that remains in each ventricle at the end of systole?
What is the volume of blood that remains in each ventricle at the end of systole?
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What is the term for the amount of blood ejected by each ventricle per stroke?
What is the term for the amount of blood ejected by each ventricle per stroke?
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What is the primary function of the cardiac muscle's automaticity?
What is the primary function of the cardiac muscle's automaticity?
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What is the main factor that contributes to the cardiac muscle's automaticity?
What is the main factor that contributes to the cardiac muscle's automaticity?
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Which of the following cardiac muscle tissues has the highest inherent rhythmicity?
Which of the following cardiac muscle tissues has the highest inherent rhythmicity?
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What is the main mechanism by which the SA node maintains its role as the primary cardiac pacemaker?
What is the main mechanism by which the SA node maintains its role as the primary cardiac pacemaker?
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Which of the following factors can increase the heart's rhythmicity or chronotropism?
Which of the following factors can increase the heart's rhythmicity or chronotropism?
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What is the main consequence of the cardiac muscle's rhythmicity or automaticity?
What is the main consequence of the cardiac muscle's rhythmicity or automaticity?
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Which of the following cardiac muscle properties is directly responsible for the heart's ability to conduct electrical impulses?
Which of the following cardiac muscle properties is directly responsible for the heart's ability to conduct electrical impulses?
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How does the cardiac muscle's contractility differ from its rhythmicity?
How does the cardiac muscle's contractility differ from its rhythmicity?
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Which part of the cardiac conduction system is responsible for initiating the heartbeat?
Which part of the cardiac conduction system is responsible for initiating the heartbeat?
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Which part of the cardiac conduction system is responsible for transmitting the electrical impulse from the atria to the ventricles?
Which part of the cardiac conduction system is responsible for transmitting the electrical impulse from the atria to the ventricles?
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Which part of the cardiac conduction system is responsible for rapidly distributing the electrical impulse throughout the ventricles?
Which part of the cardiac conduction system is responsible for rapidly distributing the electrical impulse throughout the ventricles?
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What is the function of the bundle of His in the cardiac conduction system?
What is the function of the bundle of His in the cardiac conduction system?
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Which part of the cardiac conduction system is responsible for the automaticity of the heart?
Which part of the cardiac conduction system is responsible for the automaticity of the heart?
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Which part of the cardiac conduction system is responsible for the electrical potentials of the pacemaker tissues?
Which part of the cardiac conduction system is responsible for the electrical potentials of the pacemaker tissues?
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Which part of the cardiac conduction system is responsible for the electrical potentials of the cardiac muscle fibers?
Which part of the cardiac conduction system is responsible for the electrical potentials of the cardiac muscle fibers?
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Which part of the cardiac conduction system is responsible for the rhythmicity of the heart?
Which part of the cardiac conduction system is responsible for the rhythmicity of the heart?
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What is the effect of greater initial length of cardiac muscle fiber (End diastolic volume, EDV) on the force of contraction?
What is the effect of greater initial length of cardiac muscle fiber (End diastolic volume, EDV) on the force of contraction?
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What does afterload refer to in the context of heart function?
What does afterload refer to in the context of heart function?
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What happens to the initial velocity of shortening of cardiac muscle when afterload increases?
What happens to the initial velocity of shortening of cardiac muscle when afterload increases?
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What does contractility refer to in the context of heart function?
What does contractility refer to in the context of heart function?
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What phenomenon describes gradual increases in strength of cardiac muscle contraction due to repeated stimulation (increase in heart rate)?
What phenomenon describes gradual increases in strength of cardiac muscle contraction due to repeated stimulation (increase in heart rate)?
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What effect does sympathetic nervous system stimulation have on cardiac muscle contraction?
What effect does sympathetic nervous system stimulation have on cardiac muscle contraction?
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Which physical factor has a positive inotropic effect on cardiac muscle contraction?
Which physical factor has a positive inotropic effect on cardiac muscle contraction?
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Which chemical substance has a positive inotropic effect on cardiac muscle contraction?
Which chemical substance has a positive inotropic effect on cardiac muscle contraction?
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What is the duration of the relative refractory period (RRP) in cardiac muscle?
What is the duration of the relative refractory period (RRP) in cardiac muscle?
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What is the significance of the refractory period in cardiac muscle?
What is the significance of the refractory period in cardiac muscle?
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When does the contraction of cardiac muscle (systole) reach its maximum?
When does the contraction of cardiac muscle (systole) reach its maximum?
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When does the relaxation of cardiac muscle (diastole) start?
When does the relaxation of cardiac muscle (diastole) start?
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Which nervous system component has a negative chronotropic effect on the heart, decreasing the heart rate?
Which nervous system component has a negative chronotropic effect on the heart, decreasing the heart rate?
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What is the effect of warming (fever) on the heart rate?
What is the effect of warming (fever) on the heart rate?
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Which of the following ions, when increased, can decrease the heart rate?
Which of the following ions, when increased, can decrease the heart rate?
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Which of the following conditions or substances can decrease the heart rate?
Which of the following conditions or substances can decrease the heart rate?
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