Set 6 (Part II) Flashcards
1
Q
What are the three basic functions of the respiratory system? What is it also involved in?
A
1) Exchange gas
2) Control pH of the body
3) Protect the body from entry of pathogens
- Also involved in producing vocalization
2
Q
What is the voluntary control center of the brain? What is the involontary control center?
A
- Voluntary: cerebral cortex
- Involuntary: pneumotaxic center and apneustic center of the pons
3
Q
What signals does the pons receive? What does it relay to?
A
- Receives signals from the chemoreceptors
- Relays to the medullary rhythmicity area
4
Q
Which area of the brain can override the “automatic” control of breathing?
A
Cerebral cortex
5
Q
What areas of the medulla represent the medullary rhythmicity? What information does it relay?
A
- Inspiratory and expiratory areas
- Relay information to the respiratory muscles that drive breathing
6
Q
What is the primary trigger for chemoreceptors?
A
Changes in levels of CO2
7
Q
Which areas of breathing may be controlled?
A
Diaphragm and intercostal muscles (skeletal muscle)
8
Q
What drives the changes in pressure between atmospheric pressure and pressure in the lungs?
A
Expansion and contraction of the rib cage
9
Q
What is external respiration?
A
Filling of the lungs with air
10
Q
What is pulmonary gas exchange?
A
Exchange of gas within capillary beds
11
Q
What is pulmonary ventilation?
A
Filling of the bronchus with air
12
Q
What is internal respiration?
A
Systemic tissue and gas exchange that occurs throughout the body
13
Q
Which respiratory control centers regulate breathing?
A
- Brain
- Heart (chemoreceptor and baroreceptor)
14
Q
What are the three anatomical divisions of the respiratory system?
A
- Upper respiratory tract
- Lower respiratory tract
- Accessory structures
15
Q
What forms the upper respiratory tract?
A
- Organs located outside of the chest
- Mouth, nasal cavity, tongue, pharynx (throat), larynx (voice box)
16
Q
What is the function of the upper respiratory tract?
A
- Conducting zone
- Keeps the lower respiratory half sterile through cilia and mucus
17
Q
What are the accessory structures of the respiratory system?
A
- Diaphragm
- Intercostal muscles
- Rib cage
- Oral cavity
18
Q
Differentiate the right and left lung. Where is the cardiac notch located?
A
- Right lung has three lobes, while left lung has two
- Cardiac notch is located in the left lung because the heart points to the left
19
Q
What are the muscles of inspiration?
A
- External intercostal
- Diaphragm
20
Q
What are the muscles of expiration?
A
- Internal intercostal
- Abdominal muscles
21
Q
Which muscles function at rest?
A
- Muscles of inspiration ONLY
- Diaphragm does 75% of the work
22
Q
Which muscles function during labor?
A
- Muscles of expiration are activated
- Abdominal muscles and internal intercostal
23
Q
Which muscles are also implicated in breathing?
A
- Sternocleidomastoids
- Scalenes
24
Q
What does the trachea split into?
A
Trachea splits into right and left primary bronchi –> bronchioles
25
As the structures of the respiratory tract become smaller (trachea to bronchioles to alveolar sacs to alveoli), what tissues dominate?
- Larger structures: cartilage (ex: trachea)
| - Smaller structures: smooth muscles
26
Where does gas exchange occur?
Within alveoli
27
What is the function of the hairs lining the nose?
Serve as a filter to screen particles from the air
28
What is the function of the turbinates in the nose?
- Provide a large mucus-covered surface over which the air must travel
- Moistens the air
29
What is the function of mucus in the nose?
- Moistens the air
| - Traps particles before the air enters the respiratory system
30
What explains a stuffy nose?
Turbinates become swollen, which partially blocks breathing
31
What connects the upper and lower airways?
Pharynx (throat)
32
What does the pharynx extend from and to?
- The base of the skull
| - To the esophagus
33
What are the three parts of the pharynx?
- Nasopharynx
- Oropharynx
- Laryngopharynx
34
How is the pharynx implicated in speech?
Pharynx changes shape to produce certain vowel sounds
35
Where does choking often occur?
In the pharynx
36
What organs are located within the lower respiratory tract?
- Located within the thorax
| - Trachea, bronchial tree, lungs
37
What does the trachea connect?
The larynx to the primary bronchi
38
Which structure of the lower respiratory tract is considered to be part of the open airway?
Trachea
39
What tissues compose the trachea?
Smooth muscle in which are embedded cartilage C rings
40
What is the function of ciliated epithelium in the trachea?
- Produces mucus through goblet cells
- Captures particles
- Pushes things up into the pharynx, which is coughed out
41
What are the three layers to bronchial walls?
- Epithelial
- Smooth muscle
- Connective tissue
42
What are bronchial walls similar to?
Tracheal walls
43
What are the pores of Kohn?
- Function in communication with adjacent alveoli
- Openings between the alveolus, allowing bacteria to enter
- Involved in pathology of diseases of the lungs
44
What are the primary gas exchange structures?
Alveoli
45
Describe the subdivisions of bronchioles.
- Bronchioles
- Alveolar ducts
- Alveolar sacs
- Alveoli
46
What is the respiratory membrane?
The barrier between which gases are exchanged by alveolar air and blood
47
What does the respiratory membrane consist of?
- Alveolar epithelium
- Capillary endothelium
- Their joined basement membranes
48
What is found within the surface of the respiratory membrane inside each alveolus?
Surfactant
49
What is the function of surfactant? What cells produce it?
- Reduces surface tension
| - Produced by type II cells
50
What is inspiration?
The process of taking air into the lungs
51
What is expiration?
The process of letting air out of the lungs during a breathing cycle
52
What is the inspiration process?
- Activate phase of ventilation (contraction)
- Diaphragm contracts and moves downward
- Thoracic cavity increases in volume
53
What occurs when the thoracic cavity increases in volume?
- Decreases the intra-alveolar pressure
| - Air flows into the lungs
54
What is the expiration process?
- Diaphragm relaxes and elastic recoil of the lungs and thoracic cage
- Decreases thoracic volume and increases the intra-alveolar pressure
- Pushes air out of the lungs
55
Pulmonary ventilation must establish two gas pressure gradients. What are they?
- Pressure within alveoli of lungs is lower than atmospheric pressure to produce inspiration
- Pressure within alveoli of lungs is higher than atmospheric pressure to produce expiration
56
What are pressure gradients established by?
Changes in the size of the thoracic cavity that are produced by contraction and relaxation of muscles
57
What is the pleural space created by?
Two membranes that surround the lungs (parietal and visceral pleura)
58
Diaphragm contracts, thoracic volume _______.
increases
59
Diaphragm relaxes, thoracic volume _______.
decreases
60
What is atmospheric pressure?
The air pressure of the atmosphere outside the body's airways
61
What is alveolar pressure?
- Intrapulmonary pressure
| - Pressure at the far end of the internal airways
62
What is intrapleural pressure?
- The fluid pressure of the pleural fluid between the parietal and visceral pleura
63
What are the parietal and visceral pleura?
- Parietal: outer membrane attached to the chest wall
| - Visceral: membrane surrounding the lungs
64
Define compliance.
Ability of pulmonary tissues to stretch, making inspiration possible
65
What are the effects on alveolar, and intrapleural pressure when the diaphragm moves downwards?
- Alveolar pressure decreases
| - Intrapleural pressure decreases
66
What pressure changes are required to allow for air to move into the lungs?
Alveolar pressure must drop below atmospheric pressure
67
Expiration is caused by ________.
elastic recoil
68
What is surfactant formed from? What is it?
- Lipoprotein formed from protein and phospholipid secretions
- By type II cells in the walls of the alveolus
69
What are the functions of surfactant?
- Reduce surface tension
- Prevent alveolar collapse during exhalation
- Contributes to the ability of cells to have elastic recoil
70
What is the function of surfactant in terms of compliance?
- Surfactant acts to decrease attraction between water molecules
- Promotes the expansion of the lungs
- Acts against the tendency to recoil
71
What would the effect of a lack of surfactant be in terms of compliance?
- Water molecules would be attracted to each other
- Decreases the size of the alveolus
- Increases the tendency to recoil
72
Which ability affecting compliance is missing in premature babies?
- Type II alveolar cells, which produce surfactant
| - Mothers are given a shot to allow the baby to utilize surfactant to breathe
73
What are the primary phagocytes of the respiratory system?
Alveolar macrophages
74
What are the functions of alveolar macrophages?
- Clearing the space of infectious, toxic, or allergic particles
- Secretion of lysozyme, antimicrobial peptides and proteases
75
Exchange of gases in the lungs take place between what?
Alveolar air and blood flowing through lung capillaries
76
What are the three factors that determine the amount of oxygen that diffuses into blood?
- Total functional surface area of the respiratory membrane
- Respiratory volume
- Alveolar ventilation
77
What factor that determines the amount of oxygen that diffuses in the blood is compromised by smoking?
The reduction of the functional surface area
78
What structural surfaces must oxygen pass through to diffuse from alveolar air to blood?
- Single layer alveolar epithelial cells
- Small interstitial space for diffusion
- Single layer of endothelial cells
79
Why is blood distributed through capillaries in a thin layer?
So each red blood cell comes close to the alveolar air
80
Increased cellular respiration during exercise causes a rise in plasma _____.
CO2
81
A rise in plasma CO2 is detected by what?
- Central chemoreceptors in the brain
| - Peripheral chemoreceptors in the carotid sinus and aorta
82
The nervous system signals to respiratory muscles in response to an increase in CO2. Which muscles react?
- Effector muscles increase their contraction/relaxation cycles
- Increases the rate of respiration
- Increases the rate of CO2 loss from the body
83
What is the primary regulator of pulmonary function?
CO2, which determines the rate of the respiratory cycle
84
Sensors from the nervous system provide feedback to which center?
Medullary rhythmicity center
85
What changes influence the medullary rhythmicity area?
- O2
- CO2
- pH of arterial blood
86
What does CO2 act on? What happens if it increases, or decreases?
- Central chemoreceptors in the medulla
- Increases: faster breathing
- Decreases: slower breathing
87
What causes a decrease in pH?
Less CO2
88
What does a decrease in pH act on?
- Stimulates central chemoreceptors to slow breathing
| - Stimulates peripheral chemoreceptors in the carotid and aortic bodies
89
What does an increase or decrease of arterial O2 act on?
Has little influence if it stays above a certain level
90
How does the cerebral cortex influence breathing?
- By increasing or decreasing rate
| - By increasing or decreasing strength of respirations
91
What pathological symptoms occur in chronic bronchitis?
- Enlarged submucosal gland
- Inflammation of epithelium
- Mucus accumulation
- Hyperinflamation of alveoli
92
What is the consequence of an inflammation of the epithelium?
Narrowing of the air, which reduces respiratory volume
93
What pathological symptoms occur in asthma?
- Smooth muscle constriction
- Edema of respiratory mucosa
- Excessive mucus production obstruct airways
94
What pathological symptoms occur in emphysema?
- Enlargement and destruction of alveolar wall
- Elastin fibers are destroyed
- Oxygen-carrying capacity is significantly impact
- Requires an oxygen tank
95
Compliance in alveoli without surfactant is ____ compliance in alveoli with surfactant.
A) Greater than
B) Less than
C) Equal to
B) Less than
96
At the end of inspiration, lung volume is ____.
A) Maximum
B) Minimum
C) Moving between maximum and minimum
A) Maximum
97
At the end of expiration, intra-alveolar pressure is _____.
A) Maximum
B) Minimum
C) In between maximum and minimum
A) Maximum
98
Velocity of air flow is greatest in the _____.
A) Trachea
B) Primary bronchi
C) Secondary bronchi
D) Bronchioles
A) Trachea
| Because it has the widest circumference
99
Lung compliance decreases as people age. If nothing else changes, loss of compliance means ____.
A) The work of breathing increases
B) The lungs are easier to inflate
C) Lung elasticity decreases
D) Airway resistance during inspiration increases
A) The work of breathing increases
C) Lung elasticity decreases
D) Airway resistance during inspiration increases
100
At what point in a respiratory cycle is intrapleural pressure greatest?
```
A) Middle half of inspiration
B) Second half of inspiration
C) End of inspiration
D) During expiration
E) End of expiration
```
E) End of expiration
101
The ciliated epithelium of the trachea and bronchi ______.
A) Helps move air to the lung
B) Helps move mucus to the pharynx
C) Only beats when someone is smoking or around air-borne irritants
B) Helps move mucus to the pharynx
102
On its way into the lungs, air passes through _____.
A) Pharynx, larynx, trachea
B) Larynx, pharynx, trachea
C) Pharynx, trachea
D) Larynx, trachea
A) Pharynx, larynx, trachea
103
Which air passages of the respiratory system are collapsible?
The bronchioles
104
Where is air filtered?
- Trachea
| - Bronchi
105
Cigarette smoking paralyzes cilia in the airways an increases mucus production. Why would these effects cause smokers to develop a cough?
If cilia cannot move mucus, the mucus collecting in the airways triggers a cough reflex to clear out the mucus
106
Differentiate type I and type II alveolar cells.
- Type I alveolar cells: thin cells used for gas exchange
| - Type II alveolar cells: thicker cells that synthesize and secrete a chemical known as surfactant
107
Can lung tissue contract?
No, as it does not contain muscle fibers
108
Inspiration occurs when __________ pressure decreases.
alveolar
109
How does alveolar pressure change with inspiration and expiration?
- Beginning of inspiration: 0
- Middle of inspiration: -1
- End of inspiration/beginning of expiration: 0
- Middle of expiration: +1
- End of expiration: 0
110
What is an antagonistic muscle group in the respiratory system?
Internal and external intercostal muscles
111
A girl is trying to squeeze herself into a corset. Will she be more successful by taking a deep breath and holding it or by blowing all the air out of her lungs?
- She will be more successful if she exhales deeply
| - This will decrease her thoracic volume and pull her lower rib cage inward
112
Why would the loss of the ability to cough increase the risk of respiratory infections?
Inability to cough decreases the ability to expel the potentially harmful material trapped in airway mucus
113
How does the intrapleural pressure normally compare to atmospheric pressure?
It is normally subatmospheric
114
How does intrapleural pressure change with inspiration and expiration?
- Beginning of inspiration: -3
- End of inspiration/beginning of expiration: -6
- End of expiration/beginning of inspiration: -3
115
What happens to intrapleural and alvoelar pressures when a person hiccups?
Causes a rapid decrease in both intrapleural and alveolar pressure
116
Is the compliance and elastance of individuals with emphysema high or low? Why?
- Elastic fibers are destroyed
- High compliance (stretch easily)
- Low elastance (do not recoil to their resting position during expiration)
- They must contract their expiratory muscles to force air out that is not leaving from elastic recoil
117
Differentiate bronchoconstriction and bronchodilation.
- Bronchoconstriction: decreases the amount of fresh air that reaches the alveoli
- Bronchodilation: increases the amount of fresh air that reaches the alveoli
118
How does histamine affect the respiratory system?
- Paracrine signal released by mast cells in response to either tissue damage or an allergic reaction
- Acts as a powerful bronchoconstrictor
119
In a normal person, which contributes more to the work of breathing:
- Airway resistance or
- Lung and chest wall elastance
Normally, lung and chest wall elastance contributes more
120
How does the work required for breathing change when a surfactant is not present in the lungs?
Work increases
121
Coal miners who spent years inhaling fine coal dust have much of their alveolar surface area covered with scarlike tissue. What happens to their lung compliance as a result?
Compliance decreases
122
A cancerous lung tumor has grown into the walls of a group of bronchioles, narrowing their lumens. What has happened to the resistance of air flow in these bronchioles?
Resistance of air flow increases
123
When a person fills their lungs maximally, the volume of air in the lungs is known as the ________ capacity. When they exhale all the air they can, the volume of air left in the lungs is the _________.
- total lung capacity
| - residual volume
124
How do alveolar gases change with hypoventilation and hyperventilation?
- Hypoventilation: high CO2, low O2
| - Hyperventilation: high O2, low CO2
125
What happens to bronchioles when PCO2 decreases and PO2 increases?
Bronchioles constrict, shunting air to areas of the lungs with better blood flow
126
List four functions of the respiratory system.
- Gas exchange
- Vocalization
- pH regulation
- Protection
127
Which sets of muscles are used for normal quiet inspiration?
- External intercostals
- Scalenes
- Diaphragm
128
Which sets of muscles are used for normal quiet expiration?
- No significant muscle contraction
129
Which sets of muscles are used for active expiration?
- Internal intercostals and abdominal muscles
130
What kind of muscles are the different respiratory muscles?
They are all skeletal muscles
131
Compare and contrast compliance and elastance.
- Compliance: ability to deform in response to force
| - Elastance: ability to resume original shape after deforming force has been removed
132
Does intrapleural pressure increase or decrease during inspiration?
Decrease
133
Does alveolar pressure increase or decrease during expiration?
Increase
134
________ usually depends on elastic recoil.
Expiration
135
________ is easier when lung compliance decreases.
Expiration
136
Lung compliance increases but chest wall compliance decreases as we age. How does that affect the work required for breathing?
Work increases
137
Lung compliance increases but chest wall compliance decreases as we age. How does that affect the ease with which lungs inflate?
Lungs inflate more easily
138
Lung compliance increases but chest wall compliance decreases as we age. How does that affect lung elastance?
Elastance decreases
139
Lung compliance increases but chest wall compliance decreases as we age. How does that affect airway resistance during inspiration?
Airway resistance is not affected
140
Will pulmonary surfactant increase, decrease, or not change the work required for breathing?
Decrease
141
Will pulmonary surfactant increase, decrease, or not change lung compliance?
Increase
142
Will pulmonary surfactant increase, decrease, or not change surface tension in the alveoli?
Decrease
143
What is the function of the epiglottis?
Covers the larynx and directs the food to the esophagus for digestion to avoid choking
144
What pathology causes emphysema?
- Destruction of alveoli means less surface area for gas exchange
- PO2 is low in endothelial cells
145
What pathology causes asthma?
- Increased airway resistance (bronchioles constricted) decreases alveolar ventilation
- PO2 is low in alveoli
- PO2 is low endothelial cells
146
A lack of _______ would cause lung collapse.
surfactant
147
What does surfactant promote? What does it act against?
- Promotes the expansion of the lungs
| - Acts against the tendency to recoil
148
In ventilation-perfusion matching, increased CO2 causes bronchioles to __________.
A) dilate and increased O2 causes pulmonary arterioles to constrict
B) dilate and decreased O2 causes pulmonary arterioles to constrict
C) constrict
D) constrict and decreased O2 causes pulmonary arterioles to dilate
B) dilate and decreased O2 causes pulmonary arterioles to constrict
149
Where does the most airway resistance in our respiratory system occur?
A) the trachea and bronchi
B) the alveoli
C) the intercostals and scalenes
D) the bronchioles
A) the trachea and bronchi
150
Alveolar ventilation refers to the movement of __________.
A) air into and out of the alveoli
B) air into and out of the lungs
C) dissolved gases from the blood to the alveoli
D) dissolved gases from the alveoli to the blood
A) air into and out of the alveoli
151
The respiratory tract is lined with?
A) Simple squamous epithelium
B) Stratified cuboidal epithelium
C) Pseudostratified ciliated columnar epithelium
D) Simple ciliated columnar epithelium
C) Pseudostratified ciliated columnar epithelium
152
Respiratory rate falls as carbon dioxide rises
A) True
B) False
B) False
153
What occurs to bronchioles and pulmonary arteries when PCO2 increases and PO2 decreases?
- Bronchioles: dilate
| - Pulmonary arteries: constrict
154
What occurs to bronchioles and pulmonary arteries when PCO2 decreases and PO2 increases?
- Bronchioles: constrict
| - Pulmonary arteries: dilate
