ECG and Cycle

Question 1

P

Answer 1

Atrial excitation

Question 2

QRS

Answer 2

ventricle excitation

Question 3

T

Answer 3

End of ventricular excitation

Question 4

Phase 4

Answer 4

Rectifier channels leak K out

Question 5

The greater the preload and stretching of the sarcomeres

Answer 5

the more SV

Question 6

In cardiac muscle, the fast depolarization phase of the action potential is the result of

Answer 6

increased membrane permeability to sodium ions.

Question 7

The long plateau phase of the cardiac muscle action potential is due to

Answer 7

Calcium channels remaining open

Question 8

The normal pacemaker of the heart is located in

Answer 8

the SA node

Question 9

Abnormally slow depolarization of the ventricles would most change the shape of the ________ in an ECG tracing.

Answer 9

QRS complex

Question 10

As a result of the long refractory period in the cardiac action potential, cardiac muscle CANNOT exhibit

Answer 10

Tetany

Question 11

If the pacemaker cells in the SA node become more permeable to potassium ions, the

Answer 11

HR will decrease and cells with HYPERPOLARIZE

Question 12

If the connection between the SA node and AV node becomes blocked, A) the ventricles will beat faster.

Answer 12

the ventricles beat more slowly

Question 13

Components of the conducting system of the heart. (in order)

Answer 13

1. SA node
2. Atrial depolarization
3. AV node
4. AV bundle of His
5. Bundle branches (Left and Right)
6. Purkinje fibers
7. Ventricular repolarization

Question 14

The P wave of the electrocardiogram is a signal from

Answer 14

Depolarization of the atria

Question 15

If there is a complete block between the SA node and the AV node, how would the ECG be affected?

Answer 15

Rate of P waves will be faster than the QRS complexes

Question 16

Depolarization of the ventricles is represented on an electrocardiogram by the

Answer 16

QRS complex

Question 17

The T wave on an ECG tracing represents

Answer 17

Ventricular Repolarization

Question 18

Pacemaker cells isolated from the SA node generate action potentials at ________ beats per minute.

Answer 18

80-100

Question 19

Depolarization of the atria corresponds to the EKG’s

Answer 19

P wave.

Question 20

Cardiac muscles have specialized

Answer 20

Gap junctions in cardiac muscle not found in skeletal or smooth muscles.

Question 21

The structures responsible for distributing excitation to the contractile cells are

Answer 21

Conducting cells

Question 22

Collectively, the conducting cells that carry the impulse from the SA node to the AV node is known as the

Answer 22

Internodal pathway

Question 23

The AV node delay is beneficial because

Answer 23

t allows time for the atria to contract.

Question 24

The first heart sound (“lubb”) is associated with

Answer 24

closing of the atrioventricular valves.

Question 25

Considering the left ventricle, why does isov-olumetric ventricular contraction occur during ventricular systole?

Answer 25

Aortic pressure is higher than ventricular pressure and the ventricle must pressurize the blood to open the aortic valve.

Question 26

The phase in the cardiac cycle when the mitral valve is closed and the aortic valve is open is the

Answer 26

Systolic ejection phase

Question 27

During ventricular systole, the

Answer 27

AV valves are closed

Question 28

With each ventricular systole,

Answer 28

Blood pressure increases

Question 29

In mitral valve prolapse, the cusps of the mitral valve are pushed into the

Answer 29

Left atrium

Question 30

The ________ is the amount of blood in a ventricle after it has contracted and before it begins to refill.

Answer 30

End Systolic Volume

Question 31

The ________ is the volume of blood in a ventricle at the beginning of systole.

Answer 31

End-Diastolic Volume

Question 32

The amount of blood remaining in the ventricle when the semilunar valve closes is the

Answer 32

End Systolic volume

Question 33

The heart spends most of the cardiac cycle in which phase?

Answer 33

Ventricular diastole

Question 34

During the beginning of ventricular systole when the muscle is contracting but not enough pressure has built up to open the semilunar valves the heart is said to be in

Answer 34

Isovolumetric relaxation

Question 35

When heart rate increases, the time spent in all phases _______ but most of it is during _____

Answer 35

Decreases;; Diastole

Question 36

In an adult at rest, the end-diastolic volume is typically

Answer 36

130ml

Question 37

During ventricular diastole…

Answer 37

The ventricles are passively filling and atria are contracting.

Question 38

The volume of blood ejected from each ventricle during a contraction is called the

Answer 38

Stroke Volume

Question 39

ECG reading Step RRCEI

Answer 39

Rate
Rhythm
Conduction
Ectopic
Interpretation

Question 40

P wave is the

Answer 40

Atrial depolarization

Question 41

PR INTERVAL

Answer 41

Time from onset of depolarization to the onset of ventricular depolarization

Question 42

QRS complex

Answer 42

Sum of all ventricular depolarizations

Question 43

ST interval

Answer 43

Ventricular myocardium depolarized

Question 44

Qt interval

Answer 44

Electrical systole of the ventricles

Question 45

T wave

Answer 45

Ventricular repolarization

Question 46

Each tiny box is _____mm and ___sec

Answer 46

1mm ; 0.04 sec

Question 47

5 tiny boxes is ____mm and ______sec

Answer 47

5; 0.20 sec

Question 48

5 large boxes _____mm and _____sec

Answer 48

25mm 1 sec

Question 49

PR should be less than _____ boxes

Answer 49

5

Question 50

QRS complex should be less than

Answer 50

3 small boxes

Question 51

Wave heights

P wave up to

Answer 51

3mm

Question 52

Wave heights QRS at least

Answer 52

5 mm

Question 53

Wave height T wave

Answer 53

Up to 5mm

Question 54

Depolarization of atrial contractile fibers produces ____wave and tell us ___________

Answer 54

P wave ; action potential in SA node

Question 55

Depolarization of ventricular contractile fibers produce

Answer 55

QRS complex

Question 56

End of QRS complex is

Answer 56

Ventricular contraction

Question 57

Repolarization of ventricular contractile fibers produce

Answer 57

T wave

Question 58

Ventricular diastole

Answer 58

After the t wave