#1
Which structure in the heart is known as the 'pacemaker'?
#2
What does the P wave represent in an electrocardiogram (ECG)?
#3
What is the term for the spread of electrical activation through the heart muscle, leading to contraction?
#4
What condition is characterized by an abnormally slow heart rate, typically below 60 beats per minute?
#5
What effect does acetylcholine have on the heart rate?
#6
Which ion is primarily responsible for the depolarization phase of cardiac action potentials?
#7
What is the normal resting membrane potential of cardiac cells in millivolts (mV)?
#8
What is the term for the period of time during which the cardiac muscle cannot be stimulated to contract again, regardless of stimulus strength?
#9
Which of the following conditions is characterized by rapid, irregular electrical impulses in the atria, leading to ineffective atrial contractions?
#10
Which part of the cardiac conduction system delays the impulse briefly before it moves on to the ventricles?
#11
Which phase of the cardiac action potential corresponds to the plateau phase?
#12
During which phase of the cardiac action potential does rapid repolarization occur?
#13
Which phase of the cardiac action potential is associated with the opening of voltage-gated calcium channels and the influx of calcium ions?
#14
Which of the following factors can influence cardiac conduction velocity?
#15