Chapter 18 (Exam 3)

Question 1

Put the following in order of the hearts conducting system. (Purkinje fibers, AV bundle, AV node, SA node, and bundle branches.)

Answer 1

SA Node
AV Node
AV Bundle
Bundle Branches
Purkinje Fibers

Question 2

What keeps Cardiac muscle from reaching tetanus?

Answer 2

Cardiac muscle has a refractory period that lasts until the muscle is relaxed

Question 3

____ cells make up the middle layer of the heart wall.

Answer 3

Cardiac Muscle Cells

Question 4

____ activates the sympathetic neurons.

Answer 4

Cardioacceleratory center

Question 5

____ controls parasympathetic neurons.

Answer 5

Cardioinhibitory Center

Question 6

The neurons that control heart rate are located where in the cardiovascular center?

Answer 6

Hypothalamus

Question 7

____ is called the relaxation phase of the cardiac cycle.

Answer 7

Diastole

Question 8

Exchange between a blood vessel and the cells that surround it can only occur where?

Answer 8

Capillaries

Question 9

Depolarization of the ventricles is represented on a ECG by the ____.

Answer 9

QRS Complex

Question 10

Which sound is associated with the closing of the mitral valve?

Answer 10

The first heart sound “lubb”

Question 11

____ closes when the left ventricular pressure exceed the left atrial pressure.

Answer 11

Mitral Valve

Question 12

___ of ventricular systole is the phase in the cardiac cycle when the mitral valve is closed and the aortic valve is open.

Answer 12

Ventricular Ejection

Question 13

____ will not increase cardiac output?

Answer 13

Increased parasympathetic stimulation

Question 14

____ is a characteristic of the stage of rapid depolarization of cardiac muscle.

Answer 14

Massive influx of sodium ions

Question 15

Blood exits the right ventricle through the ____.

Answer 15

Pulmonary valve

Question 16

What is represented by the T wave on an ECG?

Answer 16

Ventricular Repolarization

Question 17

increased activity by the parasympathetic nervous system is caused by ____.

Answer 17

Aortic baroreceptors

Question 18

All valves are closed during what phase of ventricular systole?

Answer 18

Isovolumetric Contraction

Question 19

Blood flow is slowest where?

Answer 19

Capillaries

Question 20

Depolarization of the atria is represented by what on an ECG?

Answer 20

The P wave on an ECG

Question 21

Intercalated discs transfer what from cell to cell?

Answer 21

Action Potentials

Question 22

In what position are the AV valves during Ventricular systole?

Answer 22

Closed

Question 23

The left ventricle pumps blood to the ____.

Answer 23

Aorta

Question 24

____ opens potassium ion channes in the SA node cells and causes the pacemaker potential to depolarize more slowly, causing the heart to slow.

Answer 24

Acetylcholine

Question 25

____ collects blood and pumps it into the ventricles.

Answer 25

Atrium

Question 26

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

Answer 26

Open calcium channels

Question 27

Where does the right ventricle pump blood to?

Answer 27

Lungs

Question 28

Blood pressure is highest where?

Answer 28

Arteries

Question 29

____ is the amount of tension the contracting ventricle must produce to force open the semilunar valve and eject blood.

Answer 29

Afterload

Question 30

AV valves allow blood to flow in how many directions.

Answer 30

1

Question 31

Where is the pacemaker located?

Answer 31

SA node

Question 32

____ prevent the AV valves from reversing into the atria.

Answer 32

Papillary muscle contractions

Question 33

Isovolumetric contraction is associated with which cardiac cycle

Answer 33

Ventricular Systole

Question 34

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

Answer 34

Stroke volume

Question 35

``` What is the correct order for the flow of blood entering form the systemic circuit? Right Atrium Left Atrium Right ventricle Left Ventricle Venae Cavae Aorta Pulmonary trunk Pulmonary veins ```

Answer 35

``` Venae Cavae Right Atrium Right Ventricle Pulmonary Trunk Pulmonary veins Left atrium Left ventricle Aorta ```

Question 36

____ generate action potential that spread tot he myocardium

Answer 36

Pacemaker cells

Question 37

____ is the difference between the systolic and diastolic pressure.

Answer 37

Pulse

Question 38

Blood passes through ____ after leaving the right ventricle but, before entering the pulmonary trunk.

Answer 38

Pulmonary Valve

Question 39

What happens to the AV valves when the semilunar valves close?

Answer 39

AV Valves close

Question 40

Blood flows through what valve after leaving the venue cavae?

Answer 40

Tricuspid valve

Question 41

Decreasing the diameter of a blood vessel by half would cause the vascular resistance to (increase/decrease)?

Answer 41

Increase

Question 42

The ____ is the muscle layer of the heart?

Answer 42

Myocardium

Question 43

3 reasons that the wall of the left ventricle is thicker than the right?

Answer 43

It produces a higher pressure It pumps against greater resistance It does more work that the right

Question 44

The cusps (leaflets) of AV Valves attach directly to ____?

Answer 44

Chordae tendinae

Question 45

Blood returning to the heart form the pulmonary circuit first enters the ____.

Answer 45

Left atrium

Question 46

____ is known as the contraction phase of the cardiac cycle.

Answer 46

Systole

Question 47

Another name for the visceral pericardium is the ____.

Answer 47

Epicardium

Question 48

The ____ supply blood to the myocardium.

Answer 48

Coronary arteries

Question 49

Where is the bicuspid (mitral) valve located?

Answer 49

Between the left atrium and left ventricle