FINAL Flashcards
1
Q
Systole
A
Contraction of atriums
Eject blood
2
Q
Diastole
A
relaxation of heart
3
Q
what happens in systole
A
ventricles contract
tricuspid/mitral valves close
4
Q
what happens in diastole
A
ventricle relax and fill with blood
av valves open
5
Q
ECG
A
electrocardiogram
6
Q
P phase of EKG
A
atrial depolarization
7
Q
SA node
A
sinoatrial node
- pacemaker of heart
- sets heartbeat
- located in right atrium
- causes atria to contract
8
Q
QRS phase of ECG
A
ventricular depolarization and arterial repolarization
9
Q
T phase of EKG
A
ventricular repolarization
10
Q
AV node
A
atrioventricular node
- b/w right atrium + ventricle
- electrical impulses spread to ventricles during heartbeat
11
Q
bundle branches
A
messages travel through these to septums of heart
12
Q
perjunke fibers
A
on outer walls of ventricles
- allow for depolarization of ventricular tissues
13
Q
graph HR , SV, CO in response to incremental exercise
A
HR : increases linearly toward max
SV : increases and then plateus
40-60% VO2 max (no plateu in trained ppl)
CO: increases linearly
14
Q
how do parasympathetic factors regulate HR during exercise
A
decreases HR by inhibiting SA + AV nodes
- vagus nerve
15
Q
how do sympathetic factors regulate HR during exercise
A
increases HR by stimulating SA and AV nodes
- cardiac accelerator nerve
16
Q
what factors affect SV during exercise
A
end diastolic volume, strength of contraction
17
Q
end diastolic volume
A
volume of blood in each ventricle at end of diastole
18
Q
how does exercise influence venous return
A
- venoconstriction
- muscle pump : rhythmic skeletel muscle contractions force blood in extremities toward heart
- respiratory pump : changes in thoracic pressure pull blood toward heart
- change in pressure : difference b/w MAP and right atrial pressure
19
Q
Venoconstriction
A
under sympathetic control pushes blood toward heart
20
Q
what factos determine blood flow during exercise
A
- skeletal muscle vasodilation
- increases artery resistance
- decreased blood flow to tissues
21
Q
changes that occur to HR in a hot environment
A
increase
22
Q
changes that occur to SV in a hot environment
A
decrease
23
Q
changes that occur to CO in a hot environment
A
increase
24
Q
HR during prolonged exercise
A
gradual increase toward max
25
SV during prolonged exercise
gradual decrease due to dehydration
reduced plasma volume
26
CO during prolonged exercise
maintained at high level
27
Compare heart rate and blood pressure responses to arm and leg work at the same oxygen uptake. What factors might explain the observed differences?
both HR and blood pressure increase higher during an arm workout compared to leg
- HR Due to higher sympathetic stimulation
-BP Due to vasoconstriction of large inactive muscle mass
28
Capillaries
Microscopic vessel through which exchanges take place between the blood and cells of the body
29
deoxygenated blood flow
1. From the body
2. Superior & inferior vena cava
3. Right atrium
4. Tricuspid valve
5. Right ventricle
6. Pulmonary artery (to lungs for O2/CO2 exchange)
30
oxygenated blood flow
1. Pulmonary vein (from lungs to get O2)
2. Left atrium
3. Bicuspid (mitral) valve
4. Left ventricle
5. Aorta
6. To body
31
Myocardium
muscular, middle layer of the heart
32
myocardial infarction (MI)
Heart Attack; due to blockage in coronary blood flow preventing the O2 supply resulting in cell damage
33
Cardiac Output
The volume of blood ejected from the left side of the heart in one minute
34
Cardiac Output equation
HR x SV
35
What happens to CO during exercise
increases
36
Qmax determined by
body size and aerobic fitness
37
What happens to HR during exercise
increases
38
Maximum HR
highest HR achieved in all-out effort to volitional fatigue
39
Maximum HR equation
220-age
40
Stroke Volume (SV)
The volume of blood pumped forward with each ventricular contraction
41
What happens to SV during exercise
increase until about 40-60% then plateaus
42
During Max exercise how does a trained individual differ
A trained individual will have a higher CO, SV, and lower HR
43
Pulse Pressure
the difference between systolic and diastolic blood pressure
44
Mean Arterial Pressure (MAP)
time averaged pressure in arteries
45
MAP equation
DBP+0.33(SBP-DBP)
46
Hypertension
higher than normal blood pressure
47
Short term BP regulation
sympathetic nervous system and baroreceptors
48
increase in BP=
decreased SNS activity
49
decrease in BP=
increased SNS activity
50
long term BP regulation
Mostly controlled by kidneys via control of blood volume by hormones
51
RAAS (renin-angiotensin-aldosterone system)
Renin is released by kidneys in response to decreased blood volume & maintains blood pressure
52
Changes in BP during exercise
SBP increases linearly
DBP remains fairly constant
MAP increases linearly
53
Ejection Fraction (EF) equation
EF = SV/EDV
54
Partial Pressure equation
Blood Flow = P1-P2/Resistance
55
Frank-Starling Mechanism
A mechanism by which the stroke volume of the heart is increased by increasing the venous return of the heart (thus stretching the ventricular muscle)
56
Baroreceptors
detect changes in blood pressure
57
primary function of pulmonary system
exchange of gases between the environmental air and blood
58
secondary function of pulmonary system
plays an important role in the regulation of the acid-base balance during exercise
59
major anatomical components of pulmonary system
lungs, diaphragm, larynx & pharynx, nasal cavity, trachea, bronchial tree
60
Respiration
exchange of gas molecules through a membrane or liquid
61
Ventilation
movement of air in and out of the lungs
62
Diffusion
Movement of molecules from an area of higher concentration to an area of lower concentration
63
conducting zone
conducts air to respiratory zone, humidifies, warms, and filters air
64
components of conducting zone
trachea, bronchial tree, bronchioles
65
Respiratory Zone
exchange of gases between air and blood
66
components of respiratory zone
respiratory bronchioles and alveolar sacs
67
Ventilation/Perfusion Ratio (V/Q)
the ratio between ventilation and perfusion in the lung; matching of ventilation to perfusion optimizes gas exchange
68
Heavy exercise results in V/Q inequality (Ventilation becomes higher and blood flow also increases)
Ventilation becomes higher and blood flow also increases
69
sickle cell anemia
a genetic disorder that causes abnormal hemoglobin, resulting in some red blood cells assuming an abnormal sickle shape
70
Light exercise improves
V/Q (moves closer to 1.0)
71
Overperfusion to
base of lungs
72
Underperfusion to
apex of lungs
73
Ficks law
law stating that the net diffusion rate of a gas across a fluid membrane is proportional to the difference in partial pressure, proportional to the area of the membrane, and inversely proportional to the thickness of the membrane
74
Factors that influence the rate of diffusion across blood-gas interface in the lung
Volume of gas area for diffusion
Difference in Partial Pressure
Membrane thickness
75
the greater the difference in partial pressure
the greater rate of diffusion
76
the thinner the membrane
the higher the diffusion
77
Dalton's Law
at constant volume and temperature, the total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of the component gases
78
Chronic Obstructive Lung Disease (COPD)
Increased airway resistance
Due to Constant airway narrowing
Decreased expiratory airflow
79
Intrapulmonic pressure & Atmospheric Pressure
760 mmhg
80
Intrapleural Pressure
756 mm Hg
81
Pulmonary Ventilation
The amount of air moved in and out of the lungs per minutes (V)
82
Tidal Volume (Vt)
Amount of air that moves in and out of the lungs during a normal breath
83
breathing frequency (f)
number of breaths taken per minute
84
Alveolar Ventilation (Va)
Volume of air that reaches the respiratory zone
85
Dead Space Ventilation (VD)
Volume of air remaining in conducting airways
86
V = Va+Vd or V= Vt x f
Ventilation Equation
87
spirometry
a measurement of breathing
88
Vital Capacity (VC):
Maximal volume of air that can be expired after maximal expiration
89
Forced Expiratory volume (FEV1)
Volume of air expired in 1 seconds during maximal expiration
90
FEV1/VC ratio
≥ to 80% is normal
91
Airflow depends on
Pressure difference between two ends of the airway
Resistance of airways
92
The relationship between hemoglobin-O2 saturation and the partial pressure of O2 in the blood
hift of the graph to the right means lower saturation for given PaO2 . Shift of the graph to the left means higher saturation for given PaO2
93
What is the functional significance of the shape of the O2-hemoglobin dissociation curve?
The curve describes the non-linear tendency for oxygen to bind to hemoglobin
94
What factors affect the shape of the curve?
Ph and temp
95
Discuss the modes of transportation for CO2 in the blood
- 70% through bicarbonate
- 20 % bound of Hb
- 10% dissolved in plasma
96
Chronic Bronchitis
- Excessive mucus blocks airway
97
Emphysema
Airway collapse and increases resistance
98
Calculation of partial pressure
P air= PO2+PCO2+PN2
99
% of O2 in air
20.93%
100
% of CO2 in air
0.03
101
% of N2 in air
79.04 %
102
Oxygen is transported
via hemoglobin or dissolved in the blood
103
Each HB can transport
1.34ml O2
104
The ventilatory response in the transition from rest to constant-load submaximal exercise
ventilation increases rapidly, then a slower rise toward steady state. PO2 and PCO2 are relatively unchanged. PO2 has slight decrease and PCO2 has slight increase
105
What happens to ventilation if the exercise is prolonged and performed in a hot/humid environment?
drift upward because increased blood temp. affects respiratory control center. Higher ventilation not due to increased PCO2
106
Oxyhemoglobin Dissociation Curve
Direction of reaction depends on
the partial pressure of oxygen in the blood
Affinity (attraction to each other) between Hb and O2
107
Decreased pH=
= more acidic= right shift
108
Increased pH=
= more basic= left shift
109
Increase in body temp=
shift to the right
110
Drop in body temp
shift to left
111
2,3 DPG (diphosphoglycerate)
When levels are increased =
right shift of the curve
112
2,3 DPG (diphosphoglycerate)
When levels are decreased =
left shift of the curve
113
Myoglobin
stores oxygen in muscle cells
114
Myoglobin action
Shuttles O2 from the cell membrane to the mitochondria
115
Mb has a ________ affinity for O2 than hemoglobin
higher
116
Function of Central chemoreceptors in the medulla
regulates H+ and PCO2 concentration in cerebrospinalfluid
117
Function of Peripheral chemoreceptors in aortic and carotid bodies
regulates PO2, PCO2, K+, and H+ in blood
118
Oxyhemoglobin
hemoglobin bound to oxygen
118
The control of ventilation during exercise
- Primary drive by higher brain centers
- "Fine tuned" by humoral chemoreceptors and neural feedback from muscles
119
Deoxyhemoglobin
hemoglobin without oxygen
120
Central Command Theory
initial signal to "drive" cardiovascular system comes from higher brain centers
121
Ventilary Control during exercise
Increase in ventilation, anticipatory response due to input from central command
122
Untrained Individuals Ve
Linear increase up to 50-70% VO2 max, exponential increase beyond this point
123
Trained Individuals Ve
Occurs at higher % VO2 max, because of delayed anerobic threshold
124
ventilatory threshold
the point where ventilation increases at a non-linear rate
125
hypoexmia
very low level of oxygen in the arterial blood
