Chapter 15: Cardiovascular System

Question 1

what supplies blood to tissues of the heart?

Answer 1

right and left coronary arteries

Question 2

cardiac cycle

Answer 2

• events of a heartbeat (one full)
• heart chambers function in coordinated manner
• heart actions regulated

Question 3

when atria contract…

Answer 3

ventricles relax

Question 4

when ventricles contract…

Answer 4

atria relax

Question 5

atrial systole

Answer 5

atria contract

Question 6

ventricular diastole

Answer 6

ventricles relax; fill

Question 7

atrial diastole

Answer 7

atria relax

Question 8

ventricular systole

Answer 8

ventricles contract

Question 9

what happens to the pressure in heart chambers during the cardiac cycle?

Answer 9

it rises and falls; pressure changes cause valves to open and close

Question 10

during atrial systole & ventricular diastole…

Answer 10

• ventricles relaxed
• av valves open, semilunar close
• about 70% of blood flows passively from atria into ventricles
• the remaining 30% is pushed by atrial systole into ventricles, causing ventricular pressure to rise

Question 11

during ventricular systole & atrial diastole…

Answer 11

• av valves close
• atria relax
• chordae tendineae prevent cusps of valves from bulging too far back into atria
• blood flows into atria from vena cava & pulmonary veins
• ventricular pressure increases & opens semilunar valve
• blood flows into pulmonary trunk & aorta

Question 12

heart sounds

Answer 12

lubb dupp

Question 13

lubb sound

Answer 13

• first sound
• occurs during ventricular systole
• associated with closing of av valves

Question 14

dupp sound

Answer 14

• second sound
• occurs during ventricular diastole
• associated with closing of pulmonary & aortic semilunar valves

Question 15

murmur

Answer 15

abnormal heart sound derived from incomplete closure of cusps of a valve

Question 16

auscultation

Answer 16

listening to heart/lungs with stethoscope

Question 17

functional syncitium

Answer 17

mass of merging cells that function as a unit

Question 18

2 masses in the heart

Answer 18

• atrial syncitium
• ventricular syncitium

Question 19

fibrillation

Answer 19

unorganized, out of sync contraction of cardiac muscle cells

Question 20

atrial fibrillation

Answer 20

unorganized contraction of atria

Question 21

ventricular fibrillation

Answer 21

unorganized contraction of ventricles; medical emergency

Question 22

cardiac conduction system

Answer 22

group of clumps & strands of specialized cardiac muscle tissue which initiates & distributes impulses throughout myocardium; coordinates the events of cardiac cycle

Question 23

cardiac conduction system pathway (8)

Answer 23

1. SA node
2. atrial syncitium
3. junctional fibers
4. AV node
5. AV bundle (of HIS)
6. bundle branches
7. purkinje fibers
8. ventricular syncitium

Question 24

the heart is…

Answer 24

self polarizing

Question 25

pacemaker of the heart

Answer 25

SA node

Question 26

SA node

Answer 26

sinoatrial node; pacemaker of the heart, right atrium

Question 27

AV node

Answer 27

atrioventricular node; secondary pacemaker

Question 28

junctional fibers

Answer 28

conduct impulses from SA to AV node

Question 29

internodal atrial muscle

Answer 29

conducts impulses from SA to atria

Question 30

AV bundle

Answer 30

conducts impulses rapidly between SA & bundle branches

Question 31

left & right bundle branches

Answer 31

split off from AV bundle; conduct impulses to purkinje fibers on both sides of heart

Question 32

purkinje fibers

Answer 32

large fibers that conduct impulses to ventricular myocardium

Question 33

the cardiac muscle is...

Answer 33

a whorled network

Question 34

electrocardiogram (ECG,EKG)

Answer 34

recording of electrical changes that occur in the myocardium during the cardiac cycle; used to asses the heart's ability to conduct impulses

Question 35

deflections/waves of EKG

Answer 35

- p wave - qrs complex - t wave

Question 36

p wave

Answer 36

atrial depolarization; occurs just prior to atrial contraction

Question 37

qrs complex

Answer 37

3 waves; ventricular depolarization; occurs just prior to ventricular contraction

Question 38

t wave

Answer 38

ventricular depolarization; occurs just prior to ventricular relaxation

Question 39

what normally controls heart rate?

Answer 39

SA node

Question 40

what modifies the heart rate in response to changing conditions

Answer 40

sympathetic & parasympathetic fibers

Question 41

parasympathetic impulses

Answer 41

vagus nerve, decreased heart rate, acts on SA/AV

Question 42

sympathetic impulses

Answer 42

accelerator nerves, increased heart rate, acts on SA/AV