Deck 46: Cardiac Cycle

Question 1

The first and second heart sounds are derived from the opening of the heart valves.

Answer 1

False

Question 2

Which of the following structures of the cardiac conduction system transmits electrical signals directly to the Purkinje fibers?

A)AV node
B)Internodal fibers
C)Right and left bundle branches
D)AV bundle
E)SA node

Answer 2

C

Question 3

In the cardiac cycle, the atria relax while the ventricles are contracting.

Answer 3

True

Question 4

In the ECG pattern, how do segments differ from intervals?

A)Intervals do not include waves or intervals, while segments do.
B)Segments are much longer in duration than intervals.
C)Segments involve important cardiac cycle events, while intervals have no significance.
D)Segments do not include waves or complexes, while intervals do.
E)Intervals involve important cardiac cycle events, while segments have no significance.

Question 5

In the standard leads I, II, and III used in this lab exercise, which location is used as the ground?

A)The left ankle
B)The right wrist
C)The right ankle
D)The left wrist
E)Either wrist or either ankle can be used as the ground.

Question 6

During the cardiac cycle, ventricular depolarization and repolarization both begin at the apex of the heart and progress superiorly.

Question 7

In the ECG pattern, the P wave is soon followed by the P-Q segment, which represents

A)atrial systole.
B)ventricular diastole.
C)atrial repolarization.
D)atrial diastole.
E)ventricular systole.

Question 8

Sounds associated with the mitral valve can best be heard by listening with a stethoscope in the

A)second intercostal space, to the right of the sternum.
B)fifth intercostal space, just to the right of the sternum.
C)directly over the middle of the sternum.
D)second intercostal space, to the left of the sternum.
E)fifth intercostal space, to the left of the sternum, along the nipple line.

Question 9

During the cardiac cycle, the semilunar valves close during ventricular diastole.

Question 10

The time required for the ventricles to contract is represented by the ________ of the ECG.

A)P-Q segment
B)QRS complex
C)T wave
D)P wave
E)S-T segment

Question 11

The AV bundle and the bundle branches are located in the ________ of the heart.

A)right atrium
B)interventricular septum
C)aorta
D)left atrium
E)interatrial septum

Question 12

The AV node controls the basic rhythm of the heart, so it is called the pacemaker, but the SA node can modify heart rate when necessary.

Question 13

Which of the following events is not observed in the ECG, because it is hidden in the QRS complex?

A)Atrial depolarization
B)Ventricular repolarization
C)Atrial systole
D)Atrial repolarization
E)Ventricular depolarization

Question 14

Which of the following shows the components of the cardiac conduction system in the correct sequence?

A)AV bundle, left and right bundle branches, SA node, AV node, Purkinje fibers
B)AV node, SA node, Purkinje fibers, AV bundle, left and right bundle branches
C)SA node, AV node, AV bundle, left and right bundle branches, Purkinje fibers
D)Purkinje fibers, left and right bundle branches, AV bundle, SA node, AV node
E)SA node, Purkinje fibers, AV node, AV bundle, left and right bundle branches

Question 15

The lead arrangement known as Einthoven's triangle, which is used to record an ECG, involves placing recording electrodes on

A)both wrists and the left ankle.
B)both ankles and the right wrist.
C)both ankles and the left wrist.
D)the left and right shoulders and the navel.
E)both wrists and the right ankle.