Which of the following is TRUE concerning the specialized conduction system of the heart?
A.
Contractions of the atria are initiated at the atrioventricular node
B.
Stimulation of the vagus nerve tends to increase heart rate
C.
Activation of the ventricles is achieved by spread of the conduction impulse through the atrioventricular bundle
D.
The heart's fibrous skeleton forms a complete electrical barrier between the atria and ventricles
E.
The septomarginal trabecula carries the conduction impulse across the membranous portion of lhe interventricular septum