Cardiovascular system Flashcards
(85 cards)
1
Q
What are the 5 components of the O2 transport system?
A
- Pulmonary ventilation
- Hb concentration
- Blood volume and Q
- Peripheral blood flow
- Aerobic metabolism
2
Q
A tubes resistance is _______ proportional to the __th power of its radius.
A
inversely; 4th
3
Q
______ muscle fibers in arterioles control blood flow to capillary beds
A
smooth
4
Q
_______ pressure witting capillaries draws fluid back.
A
osmotic
5
Q
______ pressure forces fluid from capillary
A
blood
6
Q
What are the 3 key components for delivering blood to working muscles?
A
- Heart function
- Blood flow distribution (including blood pressure)
- Oxygen extraction at muscles
7
Q
Exercise = _______ overload.
A
functional
8
Q
What are 4 anatomical changes with exercise?
A
- Increase mass and volume
- Increase size left ventricle cavity
- Modest increase left ventricle wall thickness
- Increase left ventricle EDV at rest and with exercise
9
Q
_____ ______ = amount of blood ejected with each stroke
A
stroke volume
10
Q
_____ _____ = amount of blood pumped by each heart beat
A
cardiac output
11
Q
Blood flow from heart increases in ______ proportion to exercise intensity.
A
direct
12
Q
If a steady state type exercise, Q then ______ as blood flow matches exercise metabolic requirements.
A
plateaus
13
Q
When does SV approximately plateau?
A
at 50% VO2 max
14
Q
What is another formula for stroke volume?
A
EDV - ESV
15
Q
HR increases less rapidly in untrained (T/F).
A
FALSE (more)
16
Q
What is the main training response to exercise?
A
increase in SV
17
Q
What are two causes of increases pre-load?
A
- Increase with plasma volume
2. Greater blood volume
18
Q
What two hormones cause an increase in plasma volume?
A
- anti-diuretic hormone
2. aldosterone
19
Q
What are 4 results of increased pre-load?
A
- Enhances circulatory dynamics
- Enhances thermoregulatory dynamics
- Facilitates oxygen delivery to muscle during exercise
- Contributes to training-induced enlargement of left ventricle
20
Q
What 3 factors lead to enhanced cardiac filling in diastole?
A
- Increased venous return (pre-load)
- Slower heart rate
- Increased compliance of left ventricle
21
Q
Increased end-diastolic volume stretches myocardial fibers = more powerful ________ stroke when heart contracts.
A
ejection
22
Q
_____ ______ law = relationship between muscle force and resting fibre length.
A
frank-starling
23
Q
What are the 3 mechanisms that increase SV with training?
A
- Pre-load
- Enhanced cardiac filling in diastole filling
- Greater systolic emptying
24
Q
_______ = stretch and recoil of arterial cells in superficial artery
A
pulse
25
______ = results from factors that oppose blood flow.
TPR
26
What is the formula for resistance?
(lengthxviscosity)/radius^4
27
Normally, length and blood ________ do not change substantially.
viscosity
28
What can change a lot that contributes to TPR?
Radius
29
BP = ?
Q x TPR
30
______ _____ ______ estimates the work of the heart.
systolic blood pressure
31
______ ______ ______ = force that blood exerts against the arterial walls during ventricular contraction or systole.
systolic blood pressure
32
________ ______ ____ = the relaxation phase of the cardiac cycle.
diastolic blood pressure
33
________ _______ _______ = indicates peripheral resistance and ease that blood flows from the arterioles into the capillaries.
diastolic blood pressure
34
______ = the resistance the heart has to pump against
resistance
35
_______ = primarily based on blood pressure in the major arteries
after load
36
The heart and blood vessels provide a _________ response to optimize tissue perfusion and maintain blood pressure.
coordinated
37
_______ = rate of heart rate.
chronotopic
38
_______ = the force of energy of muscular contraction
iontropic
39
Extrinsic regulation of the heart = _______ by sympathetic influence, _______ by parasympathetic influence.
increased; decreased
40
Brains higher ________ central command centre continually modulate medullary activity,
somatomotor
41
_____ _____ = provides greatest control over HR.
central command
42
The HR rapidly turns on during exercise by _______ parasympathetic inhibitory input and _______ stimulating input from the central command.
decreased; increased
43
CV centre receives reflex sensory input from peripheral receptors in what 3 areas?
1. blood vessels
2. joints
3. muscles
44
What two things are located in muscles and its vasculature that monitor chemical and physical states, especially with exercise?
1. chemoreceptors
| 2. mechanoreceptors
45
Peripheral input modifies either _____ or _______ outflow to bring about appropriate CV and respiratory response to various intensities of PA.
parasympathetic; sympathetic
46
Amount of Q received by an area depends on the ______ and ______ of arterioles supplying that area.
1. number
| 2. caliber
47
What are 4 intrinsic regulation of arterioles?
1. Directly impact arteriole smooth muscle
2. Local metabolic changes
3. Local physical changes
4. Signalling via endothelial cells lining vessels
48
What are 2 extrinsic regulation of arterioles?
1. Sympathetic and parasympathetic influences
| 2. Governed by central command
49
What is blood flow at rest (mL)? What is blood flow at exercise? (mL)
5000mL; 25,000mL
50
Regulation of capillary blood flow at exercise increases what two things?
1. Increase blood flow to muscle
| 2. Increase interface for gas exchange between blood and muscle fibres
51
Venous return is very important to maintain ____ _____.
cardiac output
52
Why is there an increase in VR with exercise?
1. Muscle pump
| 2. Change in diameter of veins due to constriction from vascular smooth muscle
53
During submaximal exercise, blood flow is _______ or _____.
unchanged; lower
54
There is a _____ increase in muscle blood flow during maximal exercise.
large
55
What is the large increase in muscle blood flow during maximal exercise due to?
1. Increase in Q
2. Redistribution of blood from non-active areas
3. Increased capillarization within trained muscles
56
What are normal resting BP levels?
<120, <80
57
What are prehypertensive values?
120-139/80-89
58
What are stage 1 HTN values?
140-159/90-99
59
What are stage 2 HTN values?
> or equal to 160/> or equal to 100
60
As exercise starts, there should be a _____ increase in SBP and a _____ increase during a graded exercise test.
rapid; linear
61
Regular ______ training may reduce systolic and diastolic BP during rest and submaximal exercise.
aerobic
62
The largest reduction in blood pressure occurs in _____ pressure, particularly in ________ subjects.
diastolic; hypertensive
63
What are 4 reasons that BP ages higher with resistance type activity?
1. Straining type activity increases BP dramatically
2. Sustained muscular force compresses peripheral arterioles
3. Increased resistance to blood flow
4. Elevated work of the heart to pump against increased TPR
64
Valsalva maneuver generates compressive forces to increase _________ pressure.
Intrathoracic
65
The _______ ______ causes thin wall, low pressure thoracic veins to collapse.
thin wall
66
The valsalva maneuver causes (increased/reduced) venous return.
reduced
67
The valsalva maneuver ______ SV.
lowers
68
The decrease in SV due to the valsalva maneuver results in an ____ drop in BP.
acute
69
What is the main reason that blood pressure increases more for upper body exercises compared to lower body ?
Smaller vasculature offers greater resistance to blood flow
70
What are the 2 key mechanisms to increase supply of oxygen to working muscles?
1. increase in blood flow
| 2. greater oxygen extraction
71
___-___ difference = oxygen extraction from the arterial blood as it circulates throughout the body.
a-vO2
72
What is the a-vO2 difference at rest?
5mL/dL
73
What is the a-vO2 difference at exercise?
~18mL/dL
74
What are 4 factors affecting a-vO2 difference?
1. hemoconcetration with exercise
2. diversion of Q to active tissue
3. increase in skeletal muscle microcirculation
5. increased number and size of mito
75
Increased levels of anaerobic substrates = increased what two things?
1. higher ATP
| 2. higher PCr
76
What are 3 adaptations to short-term and immediate energy systems due to training?
1. Increased levels of anaerobic substrates
2. Increased quantity and activity of key enzymes
3. Increased capacity to generate high levels of lactate
77
What 3 things leads to increased capacity to generate high levels of lactate?
1. Increased enzymes (to buffer lactate)
2. "pain" tolerance
3. Clearance capacity
78
There is a potential for change in immediate and short-term energy systems with _______ exercise.
strenuous
79
What are 3 metabolic adaptations to long-term aerobic exercise?
1. increased mitochondrial size and number
2. Increased aerobic system enzymes
3. Increased fat and CHO catabolism
80
What are two adaptations that happen to blood lactate concentration with long term aerobic exercise?
1. decreased rate of lactate formation for given exercise intensity
2. increased lactate clearance
81
What are 4 adaptations to the long-term energy system (aerobic) with exercise?
1. Metabolic
2. Blood lactate [ ]
3. CV adaptations
4. Pulmonary adaptations
82
Q is the product of what variables?
SV and HR
83
Endurance athletes are able to achieve higher Q through large increases in what variables?
SV
84
_______ _______ is the difference in O2 content of blood between arterial blood and mixed venous blood.
a-vO2 difference
85
What is the main reason that BP is higher in upper body exercise compared to lower?
upper body vasculature is smaller in diameter than the lower
