Chapter 19 Vocab

Question 1

Pericardium

Answer 1

A double-walled sac around the heart composed of: parietal layer of serous pericardium and visceral layer of serous pericardium

Question 2

Endocardium

Answer 2

Endothelial layer of the inner myocardial surface

Question 3

Epicardium

Answer 3

Visceral layer of the serous pericardium

Question 4

Myocardium

Answer 4

Cardiac muscle layer forming the bulk of the heart

Question 5

Intercalated discs

Answer 5

Link cardiac muscle cells together mechanically and electrically

Question 6

Desmosomes

Answer 6

Protein filaments that physically connect adjacent cardiac muscle cells

Question 7

Gap junctions

Answer 7

Protein channels that allow ions to flow between adjacent cells

Question 8

Coronary vessels

Answer 8

Blood supply of the heart wall

Question 9

Coronary arteries bring

Answer 9

Oxygenated blood to myocardium

Question 10

Coronary veins collect

Answer 10

Deoxygenated blood and drain it into the coronary sinue

Question 11

Systole

Answer 11

Contraction of a heart chamber

Question 12

Diastole

Answer 12

Relaxation of the heart chamber

Question 13

S1

Answer 13

First sound occurs as AV valves close

Question 14

S2

Answer 14

Second sound occurs when semilunar valves close

Question 15

Tissue perfusion

Answer 15

The flow of blood through arteries and capillaries delivering nutrients and oxygen to cells and removing cellular waste products

Question 16

Cardiac output

Answer 16

Amount of blood pumped by a single ventricle in one minute

Question 17

Chronotropic agents

Answer 17

Factors that influence heart rate

Question 18

Positive chronotropic

Answer 18

Increase the heart rate

Question 19

Negative chronotropic agents

Answer 19

Decrease the heart rate

Question 20

Bradycardia

Answer 20

Persistently low resting heart rate in adults

Question 21

Tachycardia

Answer 21

Persistently high resting heart rate

Question 22

Stroke volume

Answer 22

Volume of blood ejected during one beat

Question 23

Contractility

Answer 23

Force of contraction

Question 24

Inotropic agents

Answer 24

Factors that affect contractility

Question 25

Electrocardiography

Answer 25

Is a science of recording and interpreting the electrical activity that precedes and is a measure of the action of heart muscles

Question 26

Electrocardiograph

Answer 26

Is a instrument for recording the changes of electrical potential occurring during the heart beat used especially in diagnosing abnormalities of heart action

Question 27

Electrocardiogram

Answer 27

(EKG or ECG) is a graphical record (on paper or screen) of the electrical waves of the heart, as registered on the electrocardiograph

Question 28

ECG (electrocardiogram)

Answer 28

Records the electrical activity of the heart, providing a record of cardiac electrical activity, as well as valuable information about the heart’s function and structure.

Question 29

Spontaneous depolarization

Answer 29

Cell membranes are naturally leaky to sodium and calcium ions

Question 30

SA Node

Answer 30

Dominant pacemaker with an intrinsic rate of 60-100 bpm

Question 31

AV Node

Answer 31

Back-up pacemaker with an intrinsic rate of 40-60 bpm

Question 32

Ventricular cells

Answer 32

Back-up pacemaker with an intrinsic rate of 20-45 bpm

Question 33

Automaticity

Answer 33

Cardiac muscle tissue contracts on its own, in the absence of neural of hormonal stimulation.

Question 34

Depolarization

Answer 34

Movement of sodium across cell membrane causing inside of the cell to become more positive resulting in contraction

Question 35

Repolarization

Answer 35

Movement of potassium across cell membranes in which the inside of cell is restored to its negative charge

Question 36

P wave

Answer 36

Atrial depolarization

Question 37

QRS

Answer 37

Ventricular depolarization

Question 38

T waves

Answer 38

Ventricular repolarization

Question 39

Bradycardia

Answer 39

Abnormally slow heart rate below 60 per min.

Question 40

Tachycardia

Answer 40

Abnormally fast heart rate above 100 per min.