Ch. 2 Key Terms

Question 1

Action potential

Answer 1

Change in electrical potential of the heart muscle when it’s stimulated

Question 2

Aorta

Answer 2

Largest artery in the body
Transports oxygenated blood from the left ventricle to the entire body

Question 3

Aortic semilunar valve

Answer 3

Located in the aorta and prevents backflow of blood into the left ventricle

Question 4

Atrioventricular (AV) node

Answer 4

Delays the electrical impulse to allow the atria to complete their contraction (atrial kick)

Question 5

Atrium (plural: atria)

Answer 5

Top two chambers of the heart

Question 6

Automaticity

Answer 6

Ability of the heart to initiate an electrical impulse without being stimulated by an independent source

Question 7

AV bundle

Answer 7

The Bundle of His

Question 8

Bachmann’s bundle

Answer 8

Structure that relays the electrical impulse from the SA node to the left atrium in a normal heart

Question 9

Bundle branches

Answer 9

Left and right Bundle Branches of the Bundle of His that conduct impulses down either side of the interventricular septum to the left and right ventricles

Question 10

Bundle of His (AV bundle)

Answer 10

Next to AV node
Provides transfer of the electrical impulse from the atria to the ventricles

Question 11

Cardiac cycle

Answer 11

Contraction and relaxation of the heart

Question 12

Chordae tendineae

Answer 12

Structures that connect the atrioventricular (tricuspid and mitral) valves to the papillary muscles and prevent them from opening in the wrong direction

Question 13

Complexes

Answer 13

Atrial or ventricular depolarizations as they appear on the ECG
Complete ECG waveforms

Question 14

Conductivity

Answer 14

Ability of the heart cells to receive and transmit and electrical impulse

Question 15

Contractility

Answer 15

The ability of the heart muscle cells to shorten in response to an electrical stimulus

Question 16

Coronary circulation

Answer 16

Circulation of blood to and from the heart muscle

Question 17

Deoxygenated blood

Answer 17

Blood that has little or minimum oxygen (oxygen-poor blood)

Question 18

Depolarization

Answer 18

Electrical activation of the cells of the heart that initiates contraction of the heart muscle

Question 19

Diastole

Answer 19

Phase of the cardiac cycle when the heart is expanding and refilling
Aka the relaxation phase

Question 20

Excitability

Answer 20

Ability of the heart muscle cells to respond to an impulse or stimulus
Aka irritability

Question 21

Interval

Answer 21

Period of time between two activities of the heart

Question 22

Interventricular septum

Answer 22

Partition or wall (septum) that divides the right and left ventricles

Question 23

Ischemia

Answer 23

Sudden loss/reduction of blood supply (oxygen) to a region of the heart tissue
Occurs due to the presence of atherosclerotic plaque, blood clot, emboli, or vascular spasms (Prinzmetal’s angina)

Question 24

Isoelectric

Answer 24

Period when the electrical tracing of the ECG is at zero or a straight line, no positive or negative deflections are seen

Question 25

Left atrium

Answer 25

Left upper chamber of the heart that receives oxygenated blood from the lungs

Question 26

Left ventricle

Answer 26

Left lower chamber of the heart, which pumps oxygenated blood throughout the body Biggest and strongest chamber (workhorse of the heart) bc of this role

Question 27

Mitral (bicuspid) valve

Answer 27

Valve with two cusps or leaflets located between the left atrium and left ventricle Prevents backflow of blood into the atrium

Question 28

Myocardial

Answer 28

Pertaining to the heart (cardia) muscle (myo)

Question 29

Oxygenated blood

Answer 29

Blood having oxygen (oxygen-rich blood)

Question 30

Papillary muscles

Answer 30

Muscles in the ventricle that anchor the chordae tendineae and atrioventricular valves

Question 31

Parasympathetic

Answer 31

Branch of the autonomic nervous system that helps slow the heart rate

Question 32

Pericardium

Answer 32

Two-layered sac of tissue enclosing the heart

Question 33

Polarization

Answer 33

State of cellular rest in which the inside is negatively charged, and the outside is positively charged

Question 34

Pulmonary artery

Answer 34

Large artery that transports deoxygenated blood from the right ventricle to the lungs Only artery in the body that carries deoxygenated blood

Question 35

Pulmonary circulation

Answer 35

Transportation of blood to and from the lungs Blood is oxygenated in the lungs during this

Question 36

Pulmonary semilunar valve

Answer 36

Valve found in pulmonary artery that prevents backflow of blood into the right ventricle during pulmonary circulation

Question 37

Pulmonary veins

Answer 37

Transport oxygenated blood back into the left atrium of the heart Only veins in the body that carry oxygenated blood

Question 38

Purkinje fibers

Answer 38

Fibers within the heart that distribute electrical impulses from cell to cell throughout the ventricles

Question 39

Purkinje network

Answer 39

Spreads the electrical impulses throughout the ventricle by means of the Purkinje fibers

Question 40

Repolarization

Answer 40

Return of heart muscle cells to their resting electrical state, causing the heart muscle to relax

Question 41

Right atrium

Answer 41

Right upper chamber of the heart Receives deoxygenated blood from the body

Question 42

Right ventricle

Answer 42

Right lower chamber of the heart Pumps deoxygenated blood into the lungs

Question 43

Segment

Answer 43

Portion/part of the electrical tracing produced by the heart

Question 44

Semilunar valve

Answer 44

Valve with half-moon-shaped cusps that open and close, allowing blood to travel only one way Located in pulmonary artery and aorta

Question 45

Sinoatrial (SA) node

Answer 45

In the area of specialized cells in the upper right atrium that initiate the heartbeat

Question 46

Sympathetic

Answer 46

Branch of the autonomic nervous system that causes an increase in the heart rate

Question 47

Systemic circulation

Answer 47

Pathways for pumping blood throughout the body and back to the heart

Question 48

Tricuspid valve

Answer 48

Valve located between the right atrium and right ventricle Prevents backflow of blood into the right atrium

Question 49

Vena cava (plural: venae cavae)

Answer 49

Largest vein in the body, which provides a pathway for deoxygenated blood to travel from the body to the right atrium Upper portion: superior vena cava; Blood comes from head arms, and upper body Lower portion: inferior vena cava; Blood comes from the lower body and legs