Lab Exam 3 Flashcards
(120 cards)
1
Q
Define blood flow
A
the amount of blood moving through the body (or tissue) in a given period of time
2
Q
What is blood flow directly related to?
A
the change in pressure gradient
3
Q
What is blood flow indirectly related to?
A
resistance
4
Q
Define blood pressure
A
the force the blood exerts onto the wall of the blood vessel
5
Q
What is blood pressure determined by?
A
the pumping pressure of the heart & the resistance of the blood vessels
6
Q
Define peripheral resistance
A
the friction between the blood vessel & the blood
7
Q
What does peripheral resistance cause?
A
resistance to blood flow
8
Q
What affects peripheral resistance?
A
- blood viscosity (thickness of blood)
- vessel radius
- vessel length
9
Q
Define blood viscosity
A
the thickness of your blood
10
Q
What are the units of blood flow?
A
ml/sec
11
Q
Define cardiac output
A
the volume of blood pumped from the heart to the body per minute
12
Q
What is cardiac output the product of?
A
heart rate & stroke volume
13
Q
Define heart rate
A
the number of times the heart beats per minute
14
Q
Define stroke volume
A
the volume of blood pumped from the heart with each beat
15
Q
Define systole
A
the ventricular contraction period
1. isovolumic contraction
2. ventricular ejection
16
Q
Define diastole
A
period when the ventricles are NOT contracting
1. isovolumic relaxation
2. passive ventricular filling
3. atrial systole
17
Q
Define end diastolic volume
A
the volume of blood in the ventricle when atrial systole & ventricular filling are COMPLETE
18
Q
Define systolic volume
A
the volume of blood remaining in the ventricle at the end of the EJECTION phase
19
Q
Define atherosclerosis
A
the build up of fats. plaques in the walls of arteries
20
Q
How does atherosclerosis affect blood vessel radius and blood flow?
A
it will decrease the radius & decrease the blood flow
21
Q
What is the relationship between blood flow & vessel length?
A
they are indirectly related
as one increases the other decreases
22
Q
What components in the blood control viscosity?
A
plasma proteins, RBCs, WBCs, platelets (formed elements)
low levels of all of these will decrease blood viscosity
23
Q
According to physioex activities, how does increasing right flow tube radius affect flow rate, resistance, & pump rate?
A
as the right flow radius increases, resistance with decrease, and blood flow/pump rate will increase
24
Q
Using the Frank Starling Law, explain the relationship between venous return (preload) & stroke volume
A
increasing venous return will STRETCH cardiac muscle causing a greater force of contraction, thus INCREASING stroke volume
25
What intrinsic factors control stroke volume (the volume pumped out of the heart with each beat)?
contractility & preload
26
What is propranolol?
a beta-blocker medication that is used to treat high blood pressure
27
How does propranolol alter stroke volume?
it decreases blood pressure & DECREASES stroke volume
28
What is hypertension?
high blood pressure
29
How does hypertension change the pump function of the heart?
the heart will pump against the pressure, making it work harder, causing the heart muscle to thicken
30
What do myocardial cells do?
contract to pump blood
31
What do automatic cells do?
produce action potentials
32
What do automatic cells use to transport action potentials to cardiac cells?
gap junctions
33
What is the resting membrane potential for myocardial cells?
-90 mV
34
What current is responsible for phase 4 (resting) during myocardial AP?
IK1
inwardly rectifying K+ current
35
What current is responsible for phase 0 (upstroke) during myocardial AP?
INa
sodium current
36
What current is responsible for phase 1 (early repolarization) during myocardial AP?
Ito
transient outward K+ current
37
What current is responsible for phase 2 (plateau) during myocardial AP?
ICaL, Ito, IK
calcium current
transient outward K+ current
delayed rectifier K+ current
38
What current is responsible for phase 3 (final repolarization) during myocardial AP?
IK
delayed rectifier K+ current
39
Describe the effective (absolute) refractory period
no action potential can be generated
happens from the beginning of upstroke to phase 3
40
Describe the relative refractory period
a strong stimulus is needed for another AP
the more negative the membrane potential, the greater the AP
41
Describe extra systole
initiation of a second contraction before relaxation is completed from the first
42
What causes extra systole?
a strong secondary stimulus during the relative refractory period
43
Describe compensatory pause
a pause in systole followed by an extra systole
44
What causes compensatory pause?
an extra systole cannot occur during systole due to absolute refractory period
45
What is the resting membrane potential of cardiac autonomic cells?
-50 mV
46
What current is responsible for phase 4 (slow diastolic depolarization) of autonomic cell AP?
If, ICaT, IK
funny current, inward type T calcium current, delayed rectifier K+ current (outward movement)
47
What current is responsible for phase 0 (upstroke) of autonomic cell AP?
ICaL
inward type L calcium current
48
What current is responsible for phase 3 (repolarization) of autonomic cell AP?
IK
delayed rectifier K+ current (outward movement)
49
How does increased sympathetic activity affect the firing rate of SA node?
more POSITIVE diastolic potential creating a SHORTER phase 4
B1 receptor is activated resulting in If & ICaT
50
How does increased parasympathetic activity affect the firing rate of SA node?
more NEGATIVE diastolic potential creating a LONGER phase 4
muscarinic receptors activated resulting in IK
51
Define myocardial contractility
the force of contraction of the heart muscles
52
How does calcium argument myocardial contractility?
1. sympathetic activation increases cAMP concentrations
2. calcium levels increase
3. contractility increases
53
Define drug
a substance that affects some aspect of physiology when given to the body
54
Define endogenous compound
a substance that is NORMALLY found in the body
55
Define physiological effect of drugs
normal effect of the substances at healthy concentrations
56
Define pharmacological effect of drugs
effect of the compound when administered as a drug
57
How does pilocarpine affect heart rate?
stimulates parasympathetic activities
DECREASES HR
58
How does atropine affect heart rate & contractility?
decreases parasympathetic activities
INCREASES HR, INCREASES contractility
59
How does epinephrine affect heart rate & contractility?
activates B1-adrenergic receptors leading to an increase in cAMP
INCREASES HR, INCREASES contractility
60
How does digitalis affect contractility?
blocks Na/K pump causing a build up of Na and Ca in the cell
INCREASES contractility
61
How do calcium ions affect heart rate & contractility?
INCREASES HR, INCREASES contractility
62
How do potassium ions affect heart rate?
INCREASES HR
63
In a normal heart, the beat generated from what node dominates the HR?
SA node
64
The sympathetic nervous system releases what?
epinepherine
65
What does epinephrine bind to?
beta adrenergic receptors
66
How does epinephrine affect HR?
increases it
67
The parasympathetic nervous system releases what?
acetylcholine
68
What does acetylcholine bind to?
muscarinic receptors
69
How does acetylcholine affect HR?
decreases it
70
How does increasing calcium affect stoke volume?
increasing calcium increases contractility thus INCREASING stroke volume
71
What are the major muscles for inspiration?
diaphragm & EXTERNAL intercostal muscles
72
What are the major muscles for FORCED expiration?
abdominal wall & INTERNAL intercostal muscles
73
Differentiate between static & dynamic lung volume
both are a measurement of lung volume
time is a component in dynamic ONLY
74
What is static lung VOLUME?
the specific amount within the lung for a given parameter
75
What is static lung CAPACITY?
the SUM of 2 or more lung volumes
76
Define TV
tidal volume
the volume during normal inspiration & expiration
77
Define IRV
inspiratory reserve volume
the amount of air FORCEFULLY inspired after normal inspiration
78
Define ERV
expiratory reserve volume
the amount of air FORCEFULLY expired after normal expiration
79
Define RV
residual volume
what REMAINS after max expiration
80
Define IC
inspiratory capacity
the amount of air that can be inhaled
81
How do you calculate inspiratory capacity (IC)?
tidal volume (TV) + inspiratory reserve volume (IRV)
82
Defince VC
vital capacity
the amount of air that can be FORCEFULLY inhaled & exhaled
83
How do you calculate vital capacity (VC)?
tidal volume (TV) + inspiratory reserve volume (IRV) + expiratory reserve volume (ERV)
84
Define FRC
functional residual capacity
the amount of air left in the lung after a normal exhale
85
How do you calculate function residual capacity (FRC)?
expiratory reserve volume (ERV) + residual volume (RV)
86
Define TLC
total lung capacity
the max amount of air within the lungs
87
How do you calculate total lung capacity (TLC)?
tidal volume (TV) + expiratory reserve volume (ERV) + inspiratory reserve volume (IRV) + residual volume (RV)
ADD ALL THE VOLUMES
88
What is the function of a respirometer?
measures RESPIRATION by the changes in O2 & CO2
89
What is a spirogram?
an instrument that measures the volume of the lung
90
Describe the measurement of FEV1.0
forced expiratory volume
the amount of vital capacity that can exhaled in 1 SECOND
91
Differentiate between an obstructive lung disease & a restrictive lung disease
an OBSTRUCTIVE lung disease is an increase in airway resistance that can be measured by FEV1 but a RESTRICTIVE lung disease is lung stiffness that reduces expansion & causes a decreased in functional vital capacity
92
What does surfactant do?
reduce surface tension in the alveoli
93
What is intrapleural pressure?
the pressure that keeps the visceral & parietal pleural from separating
94
Why is intrapleural pressure negative?
a partial vacuum in the pleural sac is created by the elastic nature of the chest wall & the elastic properties/ surface tension of the alveolar fluid
95
What is a pneumothorax?
a condition when the intrapleural pressure equalizes with the atmospheric pressure
96
What is atelectasis?
a collapsed lung
97
How does pneumothorax cause atelectasis?
the loss of negative pressure causes the lungs to recoil & collapse
98
What is the primary factor that regulates ventilation?
the amount of fresh air that reaches the alveoli (alveolar ventilation)
99
How does hyperventilation affect ventilation?
ventilation EXCEEDS what the body needs causing a decrease in arterial PCO2
100
How does hypoventilation affect ventilation?
ventilation is NOT meeting what the body needs causing an increase in arterial PCO2
101
How does rebreathing affect ventilation?
CO2 is being breathed instead of O2 causing an increase in PCO2
102
In a patient with emphysema, what lung volumes change?
ERV, IRV, RV, FVC
103
What cells secrete surfactant?
alveolar type 2 cells
104
What kind of biomolecule is surfactant?
phospholipid
105
Describe the process of inhalation
1. external intercostals & diaphragm contract
2. lungs, chest wall, & ribs expand
3. sternum moves up & out
4. decrease pressure in thoracic cavity & alveoli
5. air moves in
106
Describe the process of exhalation
1. external intercostals & diaphragm relax
2. chest cavity & lungs contract (only during forced)
3. ribs & sternum depress
4. increase pressure in thoracic cavity & alveoli
5. air moves out
107
Inspiration is considered what kind of process?
active, due to the muscle contractions requiring ATP
108
During quiet breathings, expiration is considered what kind of process?
passive
109
During exercise, expiration is considered what kind of process?
active
110
Increasing the pressure gradient does what to blood flow?
increases it
111
Decreasing the pressure gradient does what to blood flow?
decreases it
112
Increasing viscosity does what to blood flow?
decreases it
113
Decreasing viscosity does what to blood flow?
increases it
114
Increasing vessel radius does what to blood flow?
increases it
115
Decreasing vessel radius does what to blood flow?
decreases it
116
Increasing vessel length does what to blood flow?
decreases it
117
Decreasing vessel length does what to blood flow?
increases it
118
Describe excitation-coupling reaction in cardiac muscle cells
1. myocardial AP opens voltage gated Ca2+ channels
2. Ca2+ entering the cell binds to SR Ca2+ release channels
3. CICR (calcium induced calcium release)
119
How do you calculate cardiac output when given stroke volume & HR?
SV x HR
120
How do you calculate stroke volume?
end diastolic volume - end systolic volume
