SA Node
Where is the SA node located?
Top right portion of the heart
T/F: The AV node acts as a pacemaker for the heart.
False -- the firing rate of the SA node suppresses the rate of firing of the AV node.
What does the bundle of His enter?
the interventricular septum
T/F: The Purkinje fibers send the electrical signal upward.
True
What is the bottom of the heart called?
The apex
Down what pathway does the SA node send its signal to the AV node?
Atrial internal pathway
The AV node is the only point of connection between...
the atria and the ventricles.
What is the interventricular septum?
The wall that separates the left and right ventricles
Where are the Purkinje fibers located?
Near the apex of the heart
What is the top of the heart called?
The base
How long does it take the signal to reach the AV node once it is sent from the SA node?
50 milliseconds
How long does the signal take to run through the AV node?
100 milliseconds
T/F: The right bundle branch is thicker.
False -- the left bundle branch is thicker
In the electrical conduction system of the heart, does the AV node or the SA node come first?
SA node
The SA node spreads the electrical signal across the contractile cells of the ____.
Atria
Why is it important that the AV node delays the electrical signal?
It allows the atria to fully contract and fill the ventricles with blood before the ventricles contract.
Why is the left bundle branch thicker?
The left ventricle has to pump blood to the entire body. The right ventricle only pumps blood to the lungs.
The SA node acts as a ____ for the heart.
Pacemaker
Where does the AV node send the electrical signal to?
Bundle of His
Where do the bundle branches send the electrical signal?
Purkinje fibers