Ch 22: Respiratory Part 1 Flashcards
(106 cards)
1
Q
What is the major function of respiration?
A
Supply body with O2 for cellular respiration; dispose of CO2, a waste product of cellular respiration
2
Q
What are the 4 respiration processes?
A
- Pulmonary ventilation
- External respiration
- Transport
- Internal respiration
3
Q
What is pulmonary ventilation?
A
Movement of air into and out of lungs
4
Q
What is external respiration?
A
O2 and CO2 exchange between lungs and blood
5
Q
What is the transport process of respiration?
A
O2 and CO2 in blood
6
Q
What is internal respiration?
A
O2 and CO2 exchange between systemic blood vessels and tissues
7
Q
What are the major organs of respiratory system?
A
Nose, nasal cavity, and paranasal sinuses
Pharynx
Larynx
Trachea
Bronchi and their branches
Lungs and alveoli
8
Q
What is the respiratory zone?
A
Site of gas exchange
9
Q
What are the structures of the respiratory zone?
A
- Respiratory bronchioles
- Areolar ducts
- Alveoli
10
Q
What is the conducting zone?
A
Conducts to gas exchange sites, cleanses, warms, humidifies air
11
Q
What is the purpose of the diaphragm?
A
Promote ventilation
12
Q
Describe the pathway from air passages to respiratory zone
A
Air passages undergo 23 orders of branching → bronchial tree → tips of bronchial tree → conducting zone structures → respiratory zone structures
13
Q
Where does the trachea enter into?
A
Right and left main bronchi to hilium
14
Q
What is the difference between lobar and segmental bronchi?
A
Lobar: supply one lobe
Segmental: divide repeatedly
15
Q
What structures do the bronchus branches become?
A
Bronchioles
16
Q
Describe the passage of air from terminal bronchioles to alveolar sacs
A
Terminal bronchioles → respiratory bronchioles → alveolar ducts → alveolar sacs
17
Q
What is the alveoli?
A
Cluster of alveolar sacs that is the site of gas exchange
18
Q
How many alveoli are in the lungs?
A
300 million
19
Q
What is the purpose of alveolar and capillary walls in fused basement membranes?
A
Gas exchange across membrane by simple diffusion
20
Q
What is Type 1 alveolar cells?
A
Single layer of squamous epithelium
21
Q
What is the purpose of type 2 alveolar cell?
A
Secrete surfactant and antimicrobial proteins
22
Q
What connects to adjacent alveoli?
A
Alveolar pores
23
Q
What is the purpose of alveolar macrophages?
A
Keep alveolar surfaces sterile
24
Q
What is the purpose of alveolar pores?
A
Equalize air pressure throughout lung
25
What are components of the lungs?
1. Apex
2. Base
3. Hilium
26
Which lung is the smallest?
Left
27
What are lobules?
Smallest subdivisions visible to the naked eye served by the bronchioles and branches
28
How many lobules are in each lung?
Right: 3
## Footnote
Left: 2
29
What is pulmonary circulation?
Low pressure, high volume
30
What is the purpose of pulmonary arteries?
Deliver systemic venous blood to lungs for oxygenation
31
What is the purpose for pulmonary veins?
Carry oxygenated blood from respiratory zones to heart
32
What enzyme is carried in the lungs to activate blood pressure hormone?
Angiotensin-converting enzyme
33
What is the purpose of bronchial arteries?
Provides oxygenated blood to lung tissues
34
Are bronchial arteries pulmonary or systemic?
Systemic
35
What is the purpose of bronchial veins?
Anastomose with pulmonary veins that carry venous blood back to heart
36
What is the pleurae?
Thin, doubled-layers serosa that divides the thoracic cavity into 2 pleural compartments
37
What is the parietal pleura?
On the thoracic wall superior face of diaphragm, around heart, between lungs
38
What is visceral pleura?
External lung surface
39
What is pleural fluid?
Fills pleural cavity providing lubrication and surface tension used to assist expansion and recoil
40
What is the difference between inspiration and expiration?
In: gases flow into lungs
Ex: gases exit lungs
41
What is atmospheric pressure?
Pressure exerted by air surrounding body
42
What is the average atmospheric pressure?
760mmHg = 1atm
43
What is negative respiratory pressure?
Less than Patm
44
What is positive respiratory pressure?
Greater than Patm
45
What is zero respiratory pressure?
equal to Patm
46
What is intrapulmonary pressure?
1. Pressure in alveoli
2. Fluctuates with breathing
3. Always eventually equalizes with Patm
47
What is intrapleural pressure?
1. Pressure in pleural cavity
2. Fluctuates with breathing
3. Always negative
4. Fluid level must be minimal
48
What are the opposing forces caused by promoting lung collapse?
1. Elastic recoil of lungs decreases lung size
2. Surface tension of alveolar fluid reduces alveolar size
49
What is the opposing force that cause enlarged lungs?
Elasticity of chest wall pulls thorax outward
50
What is purpose of transpulmonary pressure?
Keeps airways open, the greater the pressure the larger the lungs
51
What is atelectasis?
Lung collapse due to plugged bronchioles causing of alveoli
52
What is pneumothorax?
Air in pleural cavity
53
How is pneumothorax treated?
Treated by removing air with chest tubes → lung reinflates
54
What are the mechanical processes that depend on volume changes?
Volume change → Pressure changes
Pressure changes → gasses flow to equalize pressure
55
What is Boyle's Law?
Relationship between pressure and volume of gas, Proportional
56
What occurs during the active process of inspiration?
1. Inspiratory muscles contract
2. Thoracic volume increases → Intrapulmonary pressure drops
3. Intrapulmonary volume increases
4. Air flow into lungs by a pressure gradient
57
What is forced inspiration?
Vigorous exercise, COPD → accessory muscles → further increase in thoracic cage size
58
What is the passive process of inspiration?
1. Inspiratory muscles relax
2. Thoracic cavity volume decreases–
3. Elastic lungs recoil and intrapulmonary volume decreases → pressure increases (Ppul rises to +1 mm Hg)
4. Air flows out of lungs
59
What is forced expiration?
Active process uses abdominal and internal intercostal muscles
60
What are the 3 physical factors that influence the ease of air passage and the amount of energy required for ventilation?
1. Airway resistance
2. Alveolar surface tension
3. Lung compliance
61
What is friction?
Major-non elastic source of resistance to gas flow occurring in the airways
62
Why is airway resistance considered insignificant?
Large airway diameters in first part of conducting zone
Progressive branching of airways as get smaller, increasing total cross-sectional area
Resistance greatest in medium-sized bronchi
63
Why does resistance disappear are terminal bronchioles?
Diffusion drives gas movement
64
What occurs when there is sever constriction to obstruction of bronchioles?
Prevent life sustaining ventilation
Acute asthma attacks, stops ventilation
65
What is purpose for epinephrine in regards to bronchioles?
Dilates bronchioles reducing air resistance
66
What is the purpose for surface tension in the lungs?
Attracts liquid molecules to one another at gas liquid interface
67
How does water provide surface tension?
Coats alveolar walls → reduces them to smallest size
68
What is surfactant?
Reduces surface tension of alveolar fluid and discourages alveolar collapse
69
What is surfactant compared of?
Detergent-like lipid and protein complex produced by type II alveolar cells
70
What is infant respiratory distress syndrome?
Alveoli collapse after each breath
71
What is lung compliance?
Measure of change in lung volume that occurs with given change in trans pulmonary pressure
72
What causes lung compliance?
1. Distensibility of lung tissue
2. Surfactant that decreases alveolar surface tension
73
What diminishes lung compliance?
1. Nonelastic scar tissue replacing lung tissue
2. Reduced production of surfactant
3. Decreased flexibility of thoracic cage
74
What factors decrease total compliance of the lungs?
1. Deformities of thorax
2. Ossification of costal cartilage
3. Paralysis of intercostal muscles
75
What is tidal volume?
Amount of air inhaled or exhaled with each breath under resting conditions
76
What is inspiratory reserve volume?
Amount of air that can be forcefully inhaled after a normal tidal volume of inspiration
77
What is expiratory reserve volume?
Amount of air that can be forcefully exhaled after a normal tidal volume expiration
78
What is residual volume?
Amount of air remaining in lungs after a forced expiration
79
What is anatomical dead space?
No contribution to gas exchange
Air remaining in passageways
80
What is alveolar dead space?
Non-fucntional alveoli due to collapse or obstruction
81
What is total dead space?
Sum of anatomical and alveolar dead space
82
What is minute ventilation?
Total amount of gas flow into or out of respiratory tract in one minute
83
What is alveolar ventilation rate?
Flow of gases into and out of alveoli during a particular time
84
What are non respiratory movements?
Voluntary, modifies normal respiratory rhythm
85
What are examples of non respiratory air movements?
1. Cough
2. Sneeze
3. Crying
4. Laughing
5. Hiccups
6. Yawns
86
What is the difference between external and internal respiration?
E: Diffusion of gases in lungs
I: Diffusion of gases at body tissues
87
What is involved during external and internal respiration?
1. Physical properties of gases
2. Composition of alveolar gases
88
What is Dalton's Law?
Total pressure exerted by mixture of gases = sum of pressures exerted by each gas
89
What is partial pressure?
Pressure exerted by each gas in mixture
Directly proportional to its percentage in mixture
90
What is Henry's Law?
When gas mixtures con into contact with liquid:
1. Each gas dissolves in proportion to its partial pressure
91
What are the 2 phases that are equal to partial pressure?
1. Solubility
2. Temperature
92
Where does the gas in alveoli come from?
1. Gas exchanges in lungs
2. Humidification of air
3. Mixing of alveolar gas with each breath
93
What is external respiration?
Exchange of O2 and CO2 across respiratory membrane
94
What influences external respiration?
1. Thickness and surface area of respiratory membrane
2. Partial pressure gradients and gas solubilities
3. Ventilation-perfusion coupling
95
How does thickness assist external respiration?
Thicken if lungs become waterlogged and edematous → gas exchange inadequate
96
What is the purpose for large surface area of the lungs?
Increase gas exchange
97
What are factors that reduce surface area?
Emphysema, tumors, infammation, mucus
98
What is the Po2 of venous blood?
40 mmHg
99
What is the alveolar Po2?
104 mmHg
Drives oxygen flow to blood
100
What is the partial pressure gradient for CO2 in lungs less steep?
1. Venous blood: 45mmHg
2. Alveolar: 40 mmHg
101
What occurs when the partial pressure gradient is not steep?
CO2 diffuses in qual amounts with oxygen, 20x more soluble in plasma than O2
102
What is perfusion?
Blood flow reaching alveoli
103
What is ventilation?
Amount of gas reaching alveoli
104
What is the relationship between ventilation and perfusion?
Never balanced for all alveoli due to regional variations due to gravity and some alveolar ducts are plugged with mucus
105
When would Po2 in alveoli change diameter of arterioles?
1. Where alveolar O2 is high, arterioles dilate
2. Where alveolar O2 is low, arteriole constrict
3. Directs most blood where alveolar oxygen is high
106
When would Pco2 in alveoli cause changes in diameters of bronchioles?
1. Where alveolar CO2 is high, bronchioles dilate
2. Where alveolar CO2 is low, bronchioles constrict
3. Allows elimination of CO2 more rapidly
