Physiology Midterm Flashcards
1
Q
Main function of respiratory system
A
Suppy body with oxygen & dispose of carbon + buffer pH of body fluids
2
Q
4 stages of respiration
A
- 1) Pulmonary ventilation: moving air into and out of lungs (breathing)
- 2) external respiration: gas exchange between lungs and blood
- 3) Transport: of oxygen and carbon dioxide between lungs and tissues
- 4) Internal respiration: gas exchange between systemic blood vessels and tissues
3
Q
Nose function
A
provides airway for respiration, moistening & warming entering air, filtering inspired air, resonating chamber for speech, olfactory receptors for smell
4
Q
Nasal cavity
A
cilia cells within creates a current, mucous and trapped contaminants towards throat, cold air exposure decreases cilia movement
5
Q
Larynx
A
funnel-shaped tube of skeletal muscle. Functions include airway & route air and food to proper channels: epiglottis. functions to close off airways when swallowing food and water. Larynx also used for voice production
6
Q
3 components of Trachea
A
- 1) mucosa: made up of goblet cells and ciliated epithelium
- 2) submucosa: connective tissue deep to mucosa
- 3) adventitia: outermost layer made of C-shaped rings of hyaline cartilage
7
Q
Bronchi contain
A
cartilage
8
Q
bronchioles
A
no cartilage but has smooth muscle
9
Q
Bronchiole dilation allows…
A
more air to flow
10
Q
Type I pneumocytes
A
gas barrier cells
11
Q
Type II pneumocytes
A
surfactant producers
12
Q
Ventilation
A
act of moving air, leads to respiration
13
Q
Respiration
A
molecular exchange between physiological systems
14
Q
2 phases of ventilation
A
- inspiration: air flows into lungs
- expiration: air flows out of lungs
15
Q
Boyle’s Law
A
at constant temperature, the pressure of gas varies inversely with its volume
16
Q
Medullary respiratory center & Pontine respiratory group are responsible for what?
A
regulation of ventilation
17
Q
Neural control of ventilation, function:
A
to maintain arterial blood oxygen pressure and carbon dioxide pressure
18
Q
2 mechanisms of neural control of ventilation
A
1) efferent output from cerebral cortex: voluntary control
2) automatic efferent outputL pons and medulla oblongata
19
Q
Hypercapnia
A
greater than normal amount of carbon dioxide
20
Q
Hypocapnia
A
lower than nomral amount of carbon dioxide
21
Q
hypoxia
A
decrease in oxygen levels below normal values
22
Q
Minute ventilation
A
total air moved into and out of respiratory system each minute
23
Q
anatomic dead space
A
formed by nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, and terminal bronchioles
24
Q
physiological dead space
A
formed by anatomic dead space + volume of any alveoli in which gas exchange is less than normal
25
alveolar ventilation
volume of air availabe for gas exchange per min
26
Pleurae
double-layered sac that covers each lung
27
Parietal pleura
attached to chest wall, continues around heart and between lungs
28
visceral pleura
attached to surface of the lung
29
pleural space
between 2 layers of pleura, serves to lubricate membrane of lung and llow for movement and enlargement
30
Intrapulmonary pressure
pressure within the alveoli, increases & decreases with breathing
31
Intrapleural pressure
pressure within the pleural cavity, fluctuates with breathing, always less than intrapulmonary pressure
32
Inspiratory capacity
tidal volume + inspiratory reserve volume
33
functional residual capacity
expiratory reserve volume + residual volume (2300 mL)
34
Vital capacity
sum of inspiratory reserve volume, tidal volume, expiratory reserve volume (4600mL)
35
total lung capacity
sum of inspiratory and expiratory reserve columes + tidal and residual volume (5800 mL)
36
Lung compliance
measure the strechability of lungs
37
Lung compliance dependant on
elastic tissue elements and alveolar surface tension
38
3 components of blood
plamsa (~60%), buffy coat (<1%), erythrocytes (~40%)
39
Functions of blood
substance distribution, regulation, body protection
40
composition of plasma
- 90% water, proteins mostly produced by the liver (60% albumin, 36% globulins, 4% fibrinogen)
- nitrogenous by-products
- nutrients
- electrolytes
- respiratory gases
- hormones
41
Erythrocytes (RBC)
98.5% of all oxygen carried by blood is done by RBC
| Erythrocytoes are more than 97% hemoglobin
42
Hemoglobin can carry up to ____ oxygen molecules
Up to 4 (doesnt mean it always carries 4)
43
White blood cells functions
eliminating pathogenic agents, removal of again cells, cellular debris, wound healing, removal of cancerous cells
44
Non-specifc immune response
Innate, 1st defense
45
Specific immunity
adaptive, stronger defense to specifc pathogens
46
3 components of immune system
- 1) **Physical barriers**: **Skin** (epidermis, dermis, sebaceous glands), **Mucous membranes** (viscous mucus traps foreign matter, respiratory, renal, gastrointestinal systems)
- 2) **Leukocytes** (WBC)
- 3) **Lymphoid tissues** (thymus, bone marrow, spleen, lymph nodes, leukocytes development)
47
5 types of leukocytes (WBC)
Granulocytes (3): neutrophils, eosinophils, basophils
| Agranulocytes (2): monocytes, lymphocytes
48
Purpose of hematology analyzer
determine number of WBC/volume of blood
49
Hematology analyzer measures
1) complete blood counts
| 2) differentials
50
Neutrophils
50-80% of all leukocytes, uses phagocytosis, in circulation for 7-10 hours, life span of 1-3 days
51
Neutrophilia
elevated neutrophil count indicates bacterial or viral infection
52
Eosinphils
1-4% of all leukocytes, attaches & releases toxic proteins to parasites, can trigger allergic reaction
53
Basophils
<1% of all leukocytes, non-phagocytic cells, defense vs larger parasites through release of toxic proteins (histamine, heparin)
54
Monocytes
2-8% of all leukocytes, phagocytosis
differential cell count:
increase due to viral or parasitic infection, or cancer
decrease due to HIV, rheumatoid arthritis
migrate to tissues, increase 5-10x in size, become macrophages
55
dendritic cells
found in epithelial tissues, engulfs antigen, presents them to lymphocytes
56
Lymphocytes
20-40% of all leukocytes, increases with viral infection, 99% found in interstitial fluids
57
3 types of lymphocytes
B lymphocytes, T lymphocytes, null cells
58
B lymphocytes
differentiates into plasma cells, secretes antibodies
59
T lymphocytes
developed in thymus gland,
| 3 types: cytotoxic, helper, suppressor
60
Null cells
lack membrane components, natural killer cells
61
What are platelets (thrombocytes)
they break off megakaryocytes, contain mitochondria, granules, no nucleus, actin & myosin\
function: triggers events leading to blood clots
62
hemostasis
mechanism to stop bleeding
63
3 steps of hemostasis
1) vascular spasm
2) platelet plug formation
3) blood clot formation
64
Platelet plug formation
platelets release ADP, serotonin, epinephrin, adheres to ruptured blood vessels
65
2 things necessary for platelet plug formation
- 1) **platelets** (healthy/normal values 150-450k)
- Thrombocytopenia: less than normal levels
- Thrombocytosis: more than normal levels
- 2) **von Willebrand factor (vWF): plasma protein**
- secreted by megakaryocytes, platelets, endothelial cells.
- largest of all plasma proteins, expressed in large amounts in lung tissue because it can quickly repair capillary damage at alveoli
66
von Williebrand factor purpose
1) adhesion protein
| 2) binds factor VIII for coagulation
67
Blood clot formation
Fibrin: core of blood clot
Coagulation cascade: involves factors, most synthesized in liver, always present in plasma but in inactivated form.
ex. factor VIII vs factor VIII(a)
68
Activation of thrombin
1) intrinsic pathway: factor XII is activated (referred to as Hageman factor), contact with subendothelium leads to factor X activation, which leads to thrombin formation
2) extrinsic pathway:
- starts with tissue damage
- factor III enters plasma and forms complex with factor VII
- Factor VII becomes factor VII**a**, combines with factor III
- Which leads to factor X activation to factor X**a**
- Once factor X is activated, thrombin formation happens
69
Anticoagulant
agent that inhibits blood clotting
70
Tissue factor pathway inhibitor
produced in megakaryocytes, contained in platelets
function: bind to factor Xa leads to inactivation... results in prothrombin not being activated to become thrombin, which lowers clot formation
71
Thrombomodulin
endothelial cell transmembrane protein, binds to thrombin, can't active fibrinogen to fibrin, which leads to decreased clot formation, also activates protein C, intrinsic and extrinsic pathway inhibitor
72
Partial pressure
the larger the gradient, the more rapidly diffusion will occur
73
surface area of diffusion
reflect number of functional alveoli
74
change in diffusion barrier
decrease levels of surfactant, thickens barrier for O2 and CO2 diffusion
75
O2 and CO2 transport in blood
oxygen: alveoli to blood (external respiration) - tissue capillaries to tissues (internal respiration)
carbon dioxide: tissues to tissues capillaries - pulmonary capillaries to alveoli
76
Dalton's law of partial pressures
total pressure of any gas is equal to the sum of the partial pressures of all components of that gas
77
Dissociation curve
graph depicting the relative amount of O2 bound to hemoglobin
78
Pericardium
double-walled sac around the heart.
3 layers: fibrous, parietal & visceral serous
functions: anchor, protect heart, prevent overfilling of blood
79
epicardium
visceral layer of serous pericardium
80
myocardium
cardiac muscle layer forming bulk of heart
81
endocardium
endothelial layer of inner myocardial surface
82
Atrioventricular valve
valves lie between atria and ventricles
1) bicuspid: left atrium & ventricle
2) tricuspid: right atrium & ventricle
83
aortic semilunar valve
lies between left ventricle and aorta
84
pulmonary semilunar valve
lies between right ventricle and pulmonary trunk
85
Pulmonary circulation
short loop that runs from heart - lungs
86
Systemic circulation
routes blood through entire body - heart
87
coronary circulation
vessles that supply and drain blood to heart muscle
88
Coronary artery
Branch off ascending aorta, fill during diastole
left coronary: supplies 75% of myocardium blood
right coronary: 25%
89
Cardiac veins (coronary veins)
drains blood from heart muscle, coronary sinus
90
Myocardial infarction
caused by blockage in coronary circulation
91
2 types of cardiac muscle cells
1) autorhythmic cells: generates little force, produce action potential and sends to contractile cells to cause heart beat
2) cardiac contractile cells: force generating cells, propel blood through 3 circulation systems
92
Sinoatrial (SA) node
pacemaker of the heart, nodal cells
93
pathway of action potential through the heart
1) SA node
2) AV node
3) Bundle of His
4) right & left bundle branches
5) Purkinjie fibers
94
Pacemaker capacities...
SA: 60-100 bpm
AV: 40-60 bpm
AV bundle (bundle of His) & Purkinjie: 20-40 bpm
95
AV node
nodal cells, slow conduction
96
AV bundle
also known as bundle of His, extension into interventricular septum
97
Purkinjie fibers
fastest conduction, to ventricles
98
Skeletal muscle action potential
Resting: high extracellular Na, high intracellular K
1) Depolarization: Na influx (Na channels open, K channel start open)
2) Repolarization: K efflux (Na channels closed, K channel open)
99
Cardiac muscle action potential
Resting: high extracellular Na and Ca, high intercellular K
1) Depolarizaiton: Na influx (Na channels open, K closed, Ca start to open)
2) Early repolarization: Ca influx (Na closed, Ca open, some K open)
3) Late repolarization: K efflux (K open)
100
Autorhythmicity
self-generating action potentials in regular time intervals
101
Autorhythmicity: Pacemaker potential
Na leakage into cells causes resting membrane potential to move toward threshold (K closing)
102
Autorhythmicity: Depolarization phase
Ca channels open, K closed
103
Autorhythmicity: repolarization phase
Ca close, K open
104
P wave
atrial depolarization
| atria relaxed
105
QRS complex
ventricular depolarization and atrial repolarization
Atria contracted
ventricles start to contract
106
t wave
ventricular repolarization
ventricles contract
atria relaxed
107
Vasoconstriction
increased pressure and resistance, decreased flow
108
Vasodilation
decreased pressure and resistance, increased flow
109
Laminar flow
streamlined, outerlayer moves slowest due to friction - innerlayer moving fastest
110
Turbulent flow
non-laminar, fluid passes constriction, sharp turn, rough surface,partially responsible for heart sounds
111
Pulsatile flow
blood flow in human CV system occurs in spurts
112
Blood flow
expressed as blood volume that passes a specific point per unit time
113
Viscosity
measure of resistance of liquid to flow, largely influenced by hematocrit, dehydration can increase viscosity
114
Hematocrit
% of total blood volume composed of RBC (norm = 45%)
115
Systolic phase
period of contraction
116
Diastolic phase
period of relaxation
117
ventricular systole
period of ventricular contraction
118
ventricular diastole
period of ventricular relaxation
119
Systolic state
chamber contracts and ejects blood
Phase 1: isovolumetric contraction
Phase 2: ejection
120
Diastolic state
Chamber fills with blood
Phase 3: isovolumetric relaxation
Phase 4: passive ventricular filling
Phase 5: active ventricular filling
121
First heart sound or "lubb"
atrioventricular valves close at beginning of ventricular systole
122
Second heart sound or "dupp"
closure of aortic and pulmonary semilunar valves at beginning of ventricular diastole
123
Third heart sound (occasional)
caused by turbulent flow into ventricles
