Cardiopulmonary system Flashcards
1
Q
What is the main purpose of the cardiovascular system?
A
gas exchange
2
Q
What type of system is the cardiovascular system?
A
closed loop
3
Q
how many closed-loop systems are in the cardiovascular system? what are they?
A
2; systemic and pulmonary
4
Q
what two pumps are in series in the cardiovascular system?
A
left ventricle and the right ventricle
5
Q
what chambers of the heart are the largest?
A
ventricles
6
Q
what vessels bring blood from the system to the heart
A
veins
7
Q
what vessels send blood from the heart to the system
A
arteries
8
Q
what organ is highly oxidative?
A
the heart
9
Q
what is the ratio of cardiac sarcomeres to mitochondria?
A
1:1
10
Q
what is a key characteristic of cardiac sarcomeres?
A
striated
11
Q
a dense connective tissue plane that separates the atria from ventricles and anchors the myocardium and valves
A
cardiac skeleton
12
Q
cardiac muscle designed to squeeze
A
myocardium
13
Q
where are the semilunar valves?
A
aorta and pulmonary trunk
14
Q
where is the tricuspid valve?
A
right atrium and ventricle
15
Q
where is the bicuspid valve?
A
left atrium and ventricle
16
Q
These are inelastic cords of fibrous connective tissue that connect the papillary muscles to the tricuspid and bicuspid valves
A
chordae tendinae
17
Q
What are the pillar-like muscles seen within the cavity of the ventricles and are attached to their walls?
A
Papillary muscles
18
Q
What part of the heart encourages unidirectional blood flow?
A
Valves
19
Q
Why is the left ventricle so much larger than the right?
A
Must push blood throughout the systemic loop
20
Q
About how long does diastole last?
A
0.5 seconds
21
Q
About how long does systole last?
A
0.3 seconds
22
Q
Which portion the cardiac cycle is longer?
A
Diastole
23
Q
What is the edv?
A
Volume just before systole
24
Q
What is the esv?
A
The volume just after systole
25
What is the stroke volume (SV)?
The volume eject from the heart
26
At what point in the cardiac cycle does ventricular relaxation occur?
Diastole
27
At what point in the cardiac cycle does ventricular contraction occur?
Systole
28
At what part of the cardiac cycle does atrial contraction occur?
Diastole
29
At what part of the cardiac cycle does atrial relaxation occur?
Systole
30
Higher heart pressure occurs during which part of the cardiac cycle?
Systole
31
Lower heart pressure occurs at what part of the cardiac cycle?
Diastole
32
When the AV valves open, what portion of the heart has higher pressure?
The atria
33
When the AV vales are closed, what portion of the heart has higher pressure?
The ventricles
34
What causes the first heart sound?
AV valves closing during high ventricular pressure
35
When the semi lunar valves open, what portion of the heart has higher pressure?
The ventricles
36
When the semilunar valves close, what portion of the heart has higher pressure?
The systemic loop
37
What produces the second heart sound?
Semilunar valves closing with high systemic blood pressure
38
What is one way valves are vital?
Ensure/maintain pressure gradients
39
What changes and what remains the same between the sides of the heart during the cardiac cycle?
Pressure amount changes, heart volume is the same
40
This describes the ability of the heart to continue beating even without any neural input
Automaticity
41
What heart cells spontaneously depolarize?
SA node cardiomyocytes
42
A tiny island of cardiomyocytes found above the right atrium that spontaneously depolarize
Sinoatrial (SA) node
43
What is the spontaneous depolarization rate of the SA node?
~100 APs/min
44
Even though the heart can beat on its own, it requires what to do this?
Adequate energy (+ essential metabolic nutrients)
45
What is a big difference between the SA node cell's action potentials vs skeletal muscle/nerve aps
No resting membrane potential
46
What structure creates the SA node's pacemaker potential?
Na+/K+ ATPase (slow-leak channels)
47
What leads to gradual depolarization in SA node cells?
Faster Na+ leaking in cells
48
Cell types that have uniquely slow repolarization phases?
Cardiomyocytes
49
What are the steps of action potentiation in non-SA node cardiomyocytes?
1. Na+ channel open (in)
2. Ca2+ channel open (in)
3. Na+ channel close
4. K+ channel open (out)
4. Both K+ and Ca2+ close
50
What causes slow repolarization of non-SA node cardiomyocytes?
Ca2+ entering the cell slowly
51
A single cell or cytoplasmic mass containing several nuclei, formed by fusion of cells or by division of nuclei.
Syncytium
52
Electrically linked junctions found between cardiac muscle fibers
Intercalated discs
53
This describes the cardiac muscle fibers tendency to spread action potentials to other cells via gap junctions
Synchronous conduction
54
What are the slow Ca2+ channels in the heart muscle?
Voltage-gated Ca2+ channels
55
What are the fast Ca2+ channels in the cardiac muscle?
Ca²+ release channels
56
Where are the voltage gated Ca²+ channels found in the cardiac muscle?
Transverse tubules
57
Where are the Ca²+ release channels found in the cardiac muscle?
Sarcoplasmic reticulum
58
Are the Ca²+ channels of cardiac muscles elctromechanically coupled together?
No
59
Calcium channel blockers to reduce tachycardia block what type of channel?
The slow voltage-gated Ca²+ channels
60
A node in the right atria that delays the impulse from the SA node before passing onto the ventricles
The atrioventriclular (AV) node
61
Where does the signal from the SA node terminate?
Purkinje fibers
62
Rapid contraction of the heart occurs when the myocardium _______
Depolarizes
63
What is the purpose of the AV node?
Encourages the correct blood flow by depolarizing atria before ventricles
64
The synchronous depolarization and repolarization events of the heart can readily be observed using what?
Electrocardiogram (EKG)
65
The P wave indicates what?
Atrial depolarization
66
The QRS complex signifies what?
Ventricular depolarization, atrial repoarization
67
The T wave signifies what event?
Ventricular repolarization
68
What is the order of EKG waves?
P wave, delay, QRS complex, delay, T wave
69
The parasympathetic vagus nerve controls what function of the heart?
Heart rate
70
The sympathetic innervation of the heart controls what cardiac functions?
Both heart rate and force of contraction
71
What locations do most nerve fibers terminate in the heart?
SA node, AV node, ventricles
72
What is our normal heart rate?
70 bpm
73
What are the intrinsic action potential rates of the SA node, the AV node and the ventricles?
SA = 100, AV = 60, ventricles = 40
74
What are the three layers of vessel tissue?
1. Tunica intima
2. Tunica media
3. Tunica externa
75
What layers of vessel tissue tend to be thicker?
Tunica media then Tunica externa
76
Inner layer of blood vessels; composed of endothelium
Tunica intima
77
Middle layer of blood vessels; composed of smooth muscle
Tunica media
78
Outer layer of vessel tissue; composed of connective tissue
Tunica externa
79
An increase of distance from the heart leads to what?
Lower blood pressure
80
These portions of blood vessels allow for blood pressure changes (from artery to vein) with no chance of back flow
Precapillary sphincters
81
About how many capillaries do we have?
60 billion
82
What is the total surface area of all the capillaries in the body
1000 miles²
83
These vessels are a single layer of endothelial cells that exchange nutrients and wastes
Capillaries
84
What are the 3 types of capillaries?
1. Continuous
2. Fenestrated
3. Sinusoidal
85
A subtype of capillary with no gaps that only allows exchange of small molecules through diffusion
Continuous
86
A capillary subtype that has small gaps in cell substance that permits passage of water and small molecules
Fenestrated
87
A capillary subtype with significant gaps in cell substance and basement membrane; allows permeation of cells and large molecules
Sinusoidal
88
What is the approximate blood pressure of veins?
2 mmHg
89
What is the approximate blood pressure of arteries?
100 mmHg
90
What ensures unidirectional flow in veins?
Venous valves
91
Muscles surrounding veins that help pump blood
Skeletal muscle pumps
92
How does breathing help venous blood flow?
Inhalation increases abdominal pressure
93
What are three methods used to maintain blood flow in low pressure veins?
1. Venous valves
2. Skeletal muscle pumps
3. Breathing
