Chapter 1: Main Components of the Electrical Conduction System Flashcards
What is the Sinoatrial (SA) Node?
A bundle of specialized cardiac muscle cells.
The SA node is embedded in?
The wall of the right atrium and spontaneously generates 60 to 100 electrical impulses per minute.
What happens when the Myocardial cell receive the 60 to 100 electrical impulses?
They contract.
What does all this process determines?
The heart rate.
Where is the Atrioventricular (AV) node located?
At the junction between the atria and the ventricles.
The Atrioventricular (AV) node responds to signals from?
Sinoatrial (SA) node but generates only 40 to 60 electrical impulses per minute.
What happens if the Sinoatrial (SA) node is unable to function?
The cells of the AV node will become the new peacemakers of the heart and the heart rate becomes unusually low.
The Bundle of His cells travels along the septum that divides?
The ventricles before splitting into left and right bundle branches.
The left and right bundle branches radiate across the inner surfaces of?
The left and right ventricles.
The Purkinje Fibers are cells that disperse the electrical impulses to?
The right and left ventricles causing them to contract.
What happens when there is an interruption in the electrical signals from the SA or AV nodes?
The Purkinhje fibers can fire at a very slow and less effective rate of 15 to 40 times per minute.
