Activated when they recognize small components of antigens
A. Pacemaker cells located in the atria fire before the pacemaker cells in the ventricles. B. It takes time for hormones to diffuse from the atria to the ventricles to trigger contraction. C.The electrical signal generated in the right atrium is delayed at the AV node before passing to the ventricles. D.The ventricular muscle cells contract more slowly than the atrial muscle cells.
What do you mean can you explain more in detail please
