Flashcards in Chapter 19 Deck (54):
1
Transports blood throughout the body to allow exchange of substances, respiratory gates, nutrients and waste products between the blood of capillaries and the body's cells
Cardiovascular system
2
Carries blood away from the heart, higher blood pressure
Arteries
3
Carries blood to the heart
Veins
4
Site of substance exchange, smallest, found in tissues
Capillaries
5
Ventricles eject blood
Systole
6
ventricles relax and fill with blood
Diastole
7
What chambers of the heart are systemic
Right atrium, left ventricle
8
What chambers of the heart are pulmonary
Right ventricle, left atrium
9
Blood goes from right side of the heart to the lungs back to the left side of the heart; deoxygenated
Pulmonary circulation
10
Blood goes from the left side of the heart to the body to the right side of the heart; oxygenated
Systemic circulation
11
Form nodal tissue, 1% of the heart, specialized for generating and conducting electrical impulses in the heart
Autorrhythmic cells
12
What is the resting membrane potential for auto rhythmic cells?
-60mV
13
Located in the ceiling of the right atrium, generates action potential
SA node
14
What is the threshold for auto rhythmic cells?
-40mV
15
Comprises 99% of the heart, forms myocardium, pumps blood upon contraction
Contractile cells
16
What is the resting membrane potential for contractile cells
-90mV
17
Atrial depolarization
P Wave
18
Action potential travels down ventricular septum
Q wave
19
Ventricles contract
ST segment
20
Spread depolarization through ventricles
S wave
21
Action potential spreads through the purkinje fibers
R wave
22
Conduction through AV node and AV bundle, atria contract
PQ segment
23
Ventricles repolarize
T wave
24
Contraction of the heart
Systole
25
Relaxation of the heart, both result in 1 directional flow of blood open/close of heart valves
Diastole
26
-Both atria and ventricles in diastole
-Blood fills up atria
-AV valves open
-Semilunar valves close
-Blood moves into ventricles
Rest
27
-SA node cause AP to AV node
-Atria stimulated to contract and blood is pushed into ventricles
-Filling of ventricles are complete
Atrial Systole
28
Maximum blood volume in ventricles at end of atrial contraction
End diastolic volume
29
No change in ventricular blood volume during contraction
Isovolumetric contraction
30
Amount of blood left after contraction in ventricles
Endsystolic volume
31
Volume of blood doesn't change in ventricles during relaxation
Isovolumetric relaxation
32
-Action potential travels to AV node to inter ventricular septum to purkinje fibers
- Ventricles contract and pressure increases in ventricles
-AV valves close, all 4 valves are shut
-Atria repolarize and blood comes into atria
Early ventricular systole
33
Pressure greater in ventricles, causes semilunar valves to open and blood is ejected into vessels
Late ventricular systole
34
Ventricles repolarize, pressure decrease, semilunar valves shut, all 4 valves shut
Early ventricular diastole
35
Pressure decreases, AV valves open, everything is at rest, happens 72 times per minute
Late ventricular diastole
36
Volume of blood ejected by ventricle in one minute
Cardiac output
37
How do you find cardiac output
stroke volume x heart rate
38
What influences cardiac output?
Stroke volume and heart rate
39
Number of beats per minute
Heart rate
40
Volume of blood ejected during one beat
Stroke volume
41
How do you fine stroke volume?
End diastolic volume - end systolic volume
42
Any externa factor that changes the heart rate
Chronotopic agents
43
Gives excitatory response, increases heart rate, activates sympathetic nervous system
Positive chronotropic agent
44
Inhibitory response, decreases heart rate
negative chronotopic agents
45
Stretch of heart wall due to volume of blood before ventricular contraction
pre-load
46
Volume of blood returned to heart
venous return
47
any external factor that change stroke volume by altering contractility
inotropic agents
48
What are some examples of inotropic agents?
calcium
49
more calcium= ___ stroke volume
more
50
less calcium = ____ stroke volume
less
51
Pressure that must be exceeded before blood is ejected from the chamber, amount of pressure sitting on the semilunar valves that must be overcome before ventricular ejection can occur
Afterload
52
More pressure = ____ ejection
more
53
Increase resistance = ____ stroke volume
less
54