Heart Lecture Test Questions – Set 2

Heart Lecture Test Questions – Set 2

1. The ability to spontaneously depolarize, without nervous control:a. stenosisb. stroke volumec. diastoled. myogenicitye. systole

2. The ability to spontaneously depolarize, without nervous control, at regular intervals:a. autorhythmicityb. stroke volumec. diastoled. systolee. myogenicity

3. The normal "pacemaker" of the heart is the:a. brainb. ventriclesc. Purkinje fibersd. atrio-ventricular nodee. sino-atrial node

4. Which of the following conduction sequences is in correct order:a. AV node->internodal pathways->bundle of His->Purkinje fibers->SA node-bundle branchesb. SA node->AV node->Purkinje fibers->bundle of His->bundle branches->internodalpathwaysc. bundle of His->bundle branches->Purkinje fibers->AV node->inter-nodal pathways->SAnoded. SA node->internodal pathways->AV node->bundle or His->bundle branches->Purkinjefiberse. Purkinje fibers->bundle of His->bundle branches->internodal pathways->SA node->AVnode

5. In discussing the conducting fibers of the sino-atrial node, atrio-ventricular node, bundle of His,bundle branches and Purkinje fibers, the following may be stated (regarding one, or all ofthem):a. composed of modified cardiac muscleb. spontaneous rhythmicity and conductivity more highly developed than the rest of the heartc. initiates and transmits a depolarization wave with a rapid rate which passes through allparts of the myocardiumd. can be regulated by the autonomic (visceral) nervous systeme. all of the above

6. If the conducted depolarizations from the sino-atrial node are blocked, the ventriculardepolarizations are initiated in the:a. atrio-ventricular node, which will exhibit rhythmic depolarizations, but at a lower rateb. heart stops functioning because no depolarizations reach the ventriclesc. cardiac muscle of the atrial walls itself begin spontaneous contraction and conductiond. interatrial septume. none of the above

7. What is the effect of a heart block:a. prevents the atria from contractingb. blocks the atrio-ventricular conducting system, thus abolishing the synchronization of atriaand ventriclesc. plugs up the coronary arteries, depriving the heart muscle of oxygen and nutrients, causinglocal cell deathd. would only operate in stress conditionse. causes the ventricles to become the overall heart "pacemaker"

8. A heart block is due to:a. failure of the atrio-ventricular node to receive and/or to transmit depolarizationsb. failure of the sino-atrial node to receive stimulic. failure of the atrio-ventricular node to stimulate atrial muscled. lack of blood supply to the livere. permanent closure of a heart valve

9. The atrio-ventricular node's primary function is:a. conduction of a depolarization wave through the atriab. conduction of a depolarization wave through the ventriclesc. delay conduction from the atria to the ventricles, to allow atrial conduction to be completedd. to act as the heart's overall pacemakere. unknown

10. Which of the following has the fastest conduction speed:a. sino-atrial nodeb. internodal pathwaysc. atrio-ventricular noded. Purkinje fiberse. unmodified cardiac muscle fibers

11. The fastest conduction speed is within the:a. sino-atrial nodeb. internodal pathwaysc. atrio-ventricular noded. ventricular conducting systeme. moderator band

12. Why is the ventricular conduction system's speed so fast:a. there is much more myocardium to stimulate to contractb. depolarization is less effectivec. gravity has more effect, since this is beneath the atriad. simply because the atrial conduction is firste. it is not faster [trick question]

13. Why does ventricular depolarization and resulting contraction begin in the apex and thenprogress towards the base:a. the heart is positioned more to the left of the body's midlineb. the ventricular conducting system is more extensive than the atrial systemc. this prolongs its action, to prevent overlap with atrial systoled. this produces a milking action which squeezes the maximum amount of blood into the aortaand pulmonary trunke. there is no particular logic

14. Sequential contraction throughout the heart, from cell-to-cell conduction of depolarization, isfrom which feature:a. all-or-none responseb. myogenicityc. syncytial fibersd. independent tonee. autorhythmicity

15. Which of the following would be the most reasonable time for complete spread of thedepolarization wave from the sino-atrial node to the final ventricular contractile fibers:a. 0.09 secondb. 0.22 secondc. 1.50 secondsd. 4.50 secondse. 0.50 second

16. What is the function of the atrio-ventricular node:a. produces a strategic delay from atria to ventricles, permitting ventricular filling to becompletedb. allows one-way conduction from atria to ventriclesc. permits communication between atria and ventricular conducting systemd. can act as a secondary pacemaker if a blockage occurs with the internodal pathwayse. all of the above

17. A strategic delay in conduction from the atria to the ventricles is accomplished by:a. internodal pathwaysb. junctional fibers of the A-V nodec. bundle of Hisd. trabeculae carneaee. S-A node

18. The heart can not be tetanized because:a. it is myogenicb. it is autorhythmicc. of the long refractory period of cardiac muscle cellsd. its tone is independent of the nervous systeme. all of the above

19. The cardiac cycle is:a. the conduction phenomenab. shown by the EKGc. that the more the heart is stretched the more forceful will be its contractionsd. the alternate contraction and relaxation of the atria and the ventriclese. none of the above

20. Of the following, the longest should be:a. atrial systoleb. ventricular systolec. atrial diastoled. ventricular diastolee. none of the above, since they are all of the same duration

21. Which of the following do not occur simultaneously:a. atrial systole and ventricular systoleb. atrial diastole and ventricular diastolec. atrial diastole and ventricular systoled. atrial systole and ventricular diastolee. left ventricular systole and right ventricular systole

22. Cardiac muscle cells form an interconnected mass, permitting cell-to-cell conduction; thissituation if termed:a. syncytiumb. all-or-nonec. toned. myogenicitye. autorhythmicity

23. Which of the following occur simultaneously:a. right atrial systole and left ventricular systoleb. right atrial diastole and right ventricular diastolec. right atrial systole and right ventricular systoled. left atrial systole and left ventricular systolee. left atrial systole and right ventricular systole

24. What event is responsible for most ventricular filling:a. vibration of the moderator bandb. sucking action from ventricular diastolec. pressure from atrial systoled. atrial diastolee. none of the above

25. Atrial systole is most important for:a. filling the ventricles with the greatest volume of bloodb. preventing backflow through the A-V valvesc. preventing backflow through the semilunar valvesd. producing the necessary amount of ventricular stretching during its fillinge. all of the above