44 Questions
What term refers to the mechanism that causes cells of the SA node to depolarize rhythmically?
Pacemaker potential
What is the general term for any abnormal cardiac rhythm?
Arrhythmia
What is the role of gated ion channels and specific ion inflows and outflows in creating the nodal rhythm?
Producing pacemaker potentials
What is the mechanism that causes the twisting mode of ventricular contraction in the heart?
Tendinous cords
Which wave of the ECG correlates with atrial systole?
P wave
What is the specific term for any abnormal cardiac rhythm originating from a focus other than the SA node?
Ectopic focus
Why does the shape of a myocardial action potential differ from that of a neuron?
Different types of ion channels
What is responsible for changing conduction speeds at different points along the path of excitation in the heart?
Subendocardial conducting network
What is the significance of the plateau and unusually long refractory period of myocardial action potentials?
Supporting pumping effectiveness of the heart
What is the term for any abnormal cardiac rhythm originating from a focus other than the SA node?
Ectopic focus rhythm
Which ion is primarily responsible for the plateau and unusually long refractory period of myocardial action potentials?
Calcium
What causes cells of the SA node to depolarize rhythmically?
Pacemaker potentials
Which wave of the ECG correlates with ventricular systole?
T wave
What role do the tendinous cords play in the heart?
Preventing valvular prolapse
What is responsible for the spread of excitation through the atria, AV node, AV bundle, and bundle branches?
Subendocardial conducting network
What characteristic differentiates a nodal rhythm from a sinus rhythm?
Arising from an ectopic focus
What does the graph of pacemaker potentials depict?
Time course and voltages of the pacemaker potentials
What causes some changes in conduction speeds at different points along the path of excitation in the heart?
Myocardial action potentials
What is the term for any abnormal cardiac rhythm originating from a focus other than the SA node?
Ectopic focus
What causes the twisting mode of ventricular contraction in the heart?
Tendinous cords
Which ion is primarily responsible for the plateau and unusually long refractory period of myocardial action potentials?
Calcium
What is the general term for any abnormal cardiac rhythm?
Arrhythmia
What is responsible for changing conduction speeds at different points along the path of excitation in the heart?
Nodal rhythm
What does the graph of the time course and voltages of the pacemaker potentials depict?
How cells of the SA node depolarize rhythmically
What is the role of gated ion channels and specific ion inflows and outflows in creating the nodal rhythm?
Gated ion channels and specific ion inflows and outflows
What characteristic differentiates a nodal rhythm from a sinus rhythm?
Rate of depolarization of SA node cells
What is the general term for any abnormal cardiac rhythm originating from a focus other than the SA node?
Ectopic focus
What is the mechanism that causes cells of the SA node to depolarize rhythmically?
Pacemaker potentials
What is the significance of the plateau and unusually long refractory period of myocardial action potentials?
To support the pumping effectiveness of the heart
What is responsible for the spread of excitation through the atria, AV node, AV bundle, and bundle branches?
Subendocardial conducting network
What characteristic differentiates a nodal rhythm from a sinus rhythm?
Origin of the rhythm
What causes the twisting mode of ventricular contraction in the heart?
Tendinous cords
Which ion is primarily responsible for the plateau and unusually long refractory period of myocardial action potentials?
Calcium
What does the graph of pacemaker potentials depict?
Time course and voltages of the pacemaker potentials
What wave of the ECG correlates with ventricular systole?
T wave
What is the term for any abnormal cardiac rhythm originating from a focus other than the SA node?
Ectopic rhythm
What characteristic differentiates a nodal rhythm from a sinus rhythm?
Mechanism causing cells of the SA node to depolarize rhythmically
What does the graph of pacemaker potentials depict?
Mechanism causing cells of the SA node to depolarize rhythmically
What is responsible for changing conduction speeds at different points along the path of excitation in the heart?
Gated ion channels and specific ion inflows and outflows
What causes the twisting mode of ventricular contraction in the heart?
Gated ion channels and specific ion inflows and outflows
What ion is primarily responsible for the plateau and unusually long refractory period of myocardial action potentials?
Calcium
What wave of the ECG correlates with atrial systole?
P wave
What role do the tendinous cords play in the heart?
Preventing valvular prolapse
What is responsible for the spread of excitation through the atria, AV node, AV bundle, and bundle branches?
Gated ion channels
Test your knowledge of cardiac physiology, including the meanings of systole and diastole, characteristics of the sinus rhythm, causes of premature ventricular contraction, and more. Explore the mechanism of SA node depolarization, pacemaker potentials, and normal heart rhythm frequency.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
