he Cardiovascular System: Intrinsic Conduction System 1. The intrinsic conduction system consists of _______________ ____________ cells that initiate and distribute action potentials_______________ throughout the heart. 2. The intrinsic conduction system coordinates heart activity by determining the direction and speed of ________________. This leads to a coordinated heart contraction. 3. List the functions for the following parts of the intrinsic conduction system: a. SA Node __________________________ b. Internodal Pathway __________________________ c. AV Node __________________________ d. AV Bundle (Bundle of His) __________________________ e. Bundle Branches __________________________ f. Purkinje Fibers __________________________ 4. The action potentials spread from the autorhythmic cells of the intrinsic conduction system (electrical event) to the ______________ cells. The resulting mechanical events cause a heartbeat. 5. A tracing of the electrical activity of the heart is called a/an ________________. 6. What do the following wave forms reflect? a. P wave _______________________ b. QRS complex _______________________ c. T wave _______________________ 7. In a normal ECG wave tracing, atrial repolarization is hidden by ___________________. 8. Note: Electrical events lead to mechanical events. For example, the P wave represents ____________ depolarization, which leads to atrial _____________. 9. A left bundle branch block would have a wider than normal wave for the ____________. (Quiz section) 10. An abnormally fast heart rate (over 100 beats per minute) is called: ______________. (Quiz section)