A&P chapter 18 Questions and Correct Answers/ Latest Update / Already Graded

1 | Page



A&P chapter 18 Questions and Correct
Answers/ Latest Update / Already
Graded
Arrange these elements of the intrinsic conduction system in the

order that a depolarizing impulse travels during a normal heartbeat.


Ans: 1) SA node


2) Internodal pathways


3) AV node


4) AV bundle


5) Bundle branches


6) Purkinje fibers




1. ________: Delay(s) occurs here while atria contract


2. ________: Set(s) the pace for the entire heart


3. ________: Link(s) between the SA node and AV node


4. ________ : Electrical link(s) between atria and ventricles

,2 | Page

5. ________: Convey(s) the impulse throughout the ventricular walls


6. ________: Convey(s) the impulse down the interventricular septum


Ans: 1. AV node: Delay(s) occurs here while atria contract


2. SA node: Set(s) the pace for the entire heart


3. Internodal pathways: Link(s) between the SA node and AV node


4. AV bundle : Electrical link(s) between atria and ventricles


5. Purkinje fibers: Convey(s) the impulse throughout the ventricular walls


6. Bundle branches: Convey(s) the impulse down the interventricular

septum




Which part of the intrinsic conduction system normally initiates the

depolarizing impulse that causes a heartbeat?




A) SA node


B) AV bundle


C) AV node

, 3 | Page

D) Internodal pathway


Ans: A) SA node




Which of these structures conduct(s) action potentials the slowest?




A) Bundle branches


B) AV bundle


C) AV node


D) Purkinje fibers


Ans: C) AV node




The anatomy of the intrinsic conduction system causes contraction

of the ventricles to begin at the apex and move superiorly. Why is

this important?




A) so the atria can finish contracting before the ventricles contract