Question

Action potentials may spread from the pacemaker to myocardial cells through _____

a) Intercalated discs
b) T-tubules
c) Gap junctions
d) Sarcomeres

Answer 1

Action potentials may spread from the pacemaker to myocardial cells through intercalated discs that contain gap junctions.

Step-by-step explanation:

Cardiac muscle cells are connected through intercalated discs, which contain gap junctions and desmosomes. Gap junctions form channels between adjacent cardiac muscle fibers, allowing the depolarizing current to flow from one cell to the next. This electric coupling enables the quick transmission of action potentials and synchronized contraction of the entire heart.