Fill in the blanks:
From the SA node, impulses spread in a wave along cardiac muscle fibers of the atria. Some of these impulses will travel along an internodal athway to the __a__ node, where they ar delayed for a raction of a second. After the delay, the impulses race through the __b__ (formerly bundle of His), which enters the interventricular septum and divides into the right and left __c__. About halfway down the septum, the bundle branches terminate in the __d__ or purkinje fibers.
- a) atrioventriular node (AV node)
- b) atrioventricular bundle
- c) bundle branches
- d) subendocardial conducting network