Ch.13: The Respiratory System Flashcards
1
Q
What are the organs of the respiratory system?
A
- Nose
- Pharynx
- Larynx
- Trachea
- Bronchi
- Lungs—alveoli
2
Q
Gas exchanges between the blood and external environment occur only in the _____ of the lungs.
A
Alveoli
3
Q
Upper respiratory tract includes passageways from the _____ to _____.
A
- Nose
* Larynx
4
Q
Lower respiratory tract includes passageways from _____ to _____.
A
- Trachea
- Alveoli
- Passageways to the lungs purify, humidify, and warm the incoming air
5
Q
What is the only externally visible part of the respiratory system?
A
- Nose
- Nostrils (nares) are the route through which air enters the nose
- Nasal cavity is the interior of the nose
- Nasal septum divides the nasal cavity
6
Q
Concept Link 1
A
Recall that any area open to the outside of the body, including respiratory passages, is lined with mucous membrane (mucosa), which is a “wet,” or moist, membrane (Chapter 4, p.110).
7
Q
Olfactory receptors are located in the _____ on the superior surface.
A
• Mucosa
• The rest of the cavity is lined with respiratory mucosa, which
*Moistens air
*Traps incoming foreign particles
*Enzymes in the mucus destroy bacteria chemically
8
Q
Conchae are projections from the:
A
- Lateral walls
- Increase surface area
- Increase air turbulence within the nasal cavity
- Increased trapping of inhaled particles
9
Q
The palate separates the _____ cavity from the _____ cavity.
A
- Nasal
- Oral
- Hard palate is anterior and supported by bone
- Soft palate is posterior and unsupported
10
Q
What are paranasal sinuses?
A
Cavities within the frontal, sphenoid, ethmoid, and maxillary bones surrounding the nasal cavity
11
Q
What are the function of sinuses?
A
- Lighten the skull
- Act as resonance chambers for speech
- Produce mucus
12
Q
What is the pharynx commonly called?
A
The throat
13
Q
What is the pharynx?
A
Muscular passageway from nasal cavity to larynx
• Continuous with the posterior nasal aperture
14
Q
What are the three regions of the pharynx?
A
- Nasopharynx
- Oropharynx
- Laryngopharynx
15
Q
What is the nasopharynx?
A
Superior region behind nasal cavity
16
Q
What is the oropharynx?
A
Middle region behind mouth
17
Q
What is the laryngopharynx?
A
Inferior region attached to larynx
18
Q
_____ and _____ serve as common passageway for air and food.
A
- Oropharynx
- Laryngopharynx
- Epiglottis routes food into the posterior tube, the esophagus
19
Q
Pharyngotympanic tubes open into the:
A
- Nasopharynx
* Drain the middle ear
20
Q
Tonsils are clusters of _____ that play a role in protecting the body from _____.
A
- Lymphatic tissue
* Infection
21
Q
Pharyngeal tonsil (adenoid), a single tonsil, is located in the:
A
Nasopharynx
22
Q
Palatine tonsils (2) are located in the _____ at the end of the soft palate.
A
Oropharynx
23
Q
Lingual tonsils (2) are found at the base of the:
A
Tongue
24
Q
What is the larynx commonly called?
A
The voice box
25
What are the functions of the larynx?
* Routes air and food into proper channels
| * Plays a role in speech
26
Where is the larynx located?
Inferior to the pharynx
27
The larynx is made of eight:
* Rigid hyaline cartilages
| * Thyroid cartilage (Adam’s apple) is the largest
28
What is the epiglottis and what is its function?
* Spoon-shaped flap of elastic cartilage
* Protects the superior opening of the larynx
* Routes food to the posteriorly situated esophagus and routes air toward the trachea
* During swallowing, the epiglottis rises and forms a lid over the opening of the larynx
29
What is the function of vocal folds (true vocal cords)?
* Vibrate with expelled air
| * Allow us to speak
30
What does the glottis include?
* Vocal cords
| * Opening between the vocal cords
31
What is the trachea commonly called?
Windpipe
32
What is the trachea?
* 4-inch-long tube that connects to the larynx
| * Walls are reinforced with C-shaped rings of hyaline cartilage, which keep the trachea patent (open)
33
The main bronchi are formed by:
* Division of the trachea
| * Bronchi subdivide into smaller and smaller branches
34
Each bronchus enters the lung at the:
Hilum (medial depression)
35
Right bronchus is _____, _____, and _____ than the left.
* Wider
* Shorter
* Straighter
36
The lungs occupy the entire _____ cavity except for the central _____.
* Thoracic
* Mediastinum
* Base rests on the diaphragm
37
Apex of each lung is near the:
• Clavicle (superior portion)
38
How is each lung is divided into lobes by fissures?
* Left lung—two lobes
| * Right lung—three lobes
39
_____ covers the outer surface of the lungs.
* Serosa
* Pulmonary (visceral) pleura covers the lung surface
* Parietal pleura lines the walls of the thoracic cavity
40
_____ fills the area between layers of the lungs.
* Pleural fluid
* Allows the lungs to glide over the thorax
* Decreases friction during breathing
41
_____ fills the area between layers of the lungs.
* Pleural fluid
* Allows the lungs to glide over the thorax
* Decreases friction during breathing
42
What is the bronchial tree?
* Main bronchi subdivide into smaller and smaller branches
* Bronchial (respiratory) tree is the network of branching passageways
* All but the smallest passageways have reinforcing cartilage in the walls
* Conduits to and from the respiratory zone
* Bronchioles (smallest conducting passageways)
43
Terminal bronchioles lead into _____ structures and terminate in _____.
* Respiratory zone
| * Alveoli
44
Respiratory zone includes the:
* Respiratory bronchioles
* Alveolar ducts
* Alveolar sacs
* Alveoli (air sacs)—the only site of gas exchange
45
Conducting zone structures include:
All other passageways
46
What is alveoli?
* Simple squamous epithelial cells largely compose the walls
| * Alveolar pores connect neighboring air sacs
47
_____ cover external surfaces of alveoli
Pulmonary capillaries
48
What is respiratory membrane (air-blood barrier)?
* On one side of the membrane is air, and on the other side is blood flowing past
* Formed by alveolar and capillary walls
49
What is respiratory membrane (air-blood barrier)?
* On one side of the membrane is air, and on the other side is blood flowing past
* Formed by alveolar and capillary walls
50
What are alveolar macrophages (“dust cells”)?
Add protection by picking up bacteria, carbon particles, and other debris
51
What is a surfactant (a lipid molecule)?
* Coats gas-exposed alveolar surfaces
| * Secreted by cuboidal surfactant-secreting cells
52
What are the functions of the respiratory system?
Supply the body with oxygen
| Dispose of carbon dioxide
53
Respiration includes what four distinct events?
1. Pulmonary ventilation
2. External respiration
3. Respiratory gas transport
4. Internal respiration
54
What is pulmonary ventilation?
Moving air into and out of the lungs (commonly called breathing)
55
What is external respiration?
* Gas exchange between pulmonary blood and alveoli
* Oxygen is loaded into the blood
* Carbon dioxide is unloaded from the blood
56
What is respiratory gas transport?
Transport of oxygen and carbon dioxide via the bloodstream
57
What is internal respiration?
Gas exchange between blood and tissue cells in systemic capillaries
58
What are the mechanics of pulmonary ventilation?
* Mechanical process that depends on volume changes in the thoracic cavity
* Volume changes lead to pressure changes, which lead to the flow of gases to equalize pressure
59
Concept Link 2
Recall that pressure changes also drive other processes in the body, such as filtration (passive transport; Chapter 3, pp. 76–77) and blood flow (Chapter 11). In these processes, substances move from high to low pressure and achieve a specific function, such as membrane transport or circulation.
60
What are the two phases of pulmonary ventilation?
Inspiration = inhalation
• Flow of air into lungs
Expiration = exhalation
• Air leaving lungs
61
What are the two phases of pulmonary ventilation?
Inspiration = inhalation
• Flow of air into lungs
Expiration = exhalation
• Air leaving lungs
62
What are the mechanics of inspiration (inhalation)?
* Diaphragm and external intercostal muscles contract
* Intrapulmonary volume increases
* Gas pressure decreases
* Air flows into the lungs until intrapulmonary pressure equals atmospheric pressure
63
What are the mechanics of expiration (exhalation)?
* Largely a passive process that depends on natural lung elasticity
* Intrapulmonary volume decreases
* Gas pressure increases
* Gases passively flow out to equalize the pressure
* Forced expiration can occur mostly by contraction of internal intercostal muscles to depress the rib cage
64
What is intrapleural pressure?
* The pressure within the pleural space is always negative
* Major factor preventing lung collapse
* If intrapleural pressure equals atmospheric pressure, the lungs recoil and collapse
65
What factors affect respiratory capacity?
* Size
* Sex
* Age
* Physical condition
66
What is tidal volume (TV)?
* Normal quiet breathing
| * 500 ml of air is moved in/out of lungs with each breath
67
What is inspiratory reserve volume (IRV)?
* Amount of air that can be taken in forcibly over the tidal volume
* Usually around 3,100 milliliter
68
What is expiratory reserve volume (ERV)?
* Amount of air that can be forcibly exhaled after a tidal expiration
* Approximately 1,200 milliliter
69
What is residual volume?
* Air remaining in lung after expiration
* Cannot be voluntarily exhaled
* Allows gas exchange to go on continuously, even between breaths, and helps keep alveoli open (inflated)
* About 1,200 milliliter
70
What is vital capacity?
* The total amount of exchangeable air
* Vital capacity = TV + IRV + ERV
* 4,800 milliliter in men; 3,100 milliliter in women
71
What is dead space volume?
* Air that remains in conducting zone and never reaches alveoli
* About 150 ml
72
What is functional volume?
* Air that actually reaches the respiratory zone
| * Usually about 350 ml
73
Respiratory capacities are measured with a:
Spirometer
74
Non-respiratory air movements can be caused by _____ or _____.
* Reflexes
| * Voluntary actions
75
Examples of non-respiratory air movements include:
* Cough and sneeze—clears lungs of debris
* Crying—emotionally induced mechanism
* Laughing—similar to crying
* Hiccup—sudden inspirations
* Yawn—very deep inspiration
76
What are the two recognizable sounds that can be heard with a stethoscope?
* Bronchial sounds—produced by air rushing through large passageways such as the trachea and bronchi
* Vesicular breathing sounds—soft sounds of air filling alveoli
77
External respiration is an exchange of gases occurring between the _____ and _____ (pulmonary gas exchange).
* Alveoli
| * Pulmonary blood
78
Internal respiration is an exchange of gases occurring between the _____ and _____ (systemic capillary gas exchange).
* Blood
| * Tissue cells
79
During external respiration:
Oxygen is loaded into the blood
• Oxygen diffuses from the oxygen-rich air of the alveoli to the oxygen-poor blood of the pulmonary capillaries
Carbon dioxide is unloaded out of the blood
• Carbon dioxide diffuses from the blood of the pulmonary capillaries to the alveoli
80
How is oxygen transported in the blood?
* Most oxygen travels attached to hemoglobin and forms oxyhemoglobin (HbO2)
* A small dissolved amount is carried in the plasma
81
How is carbon dioxide transported in the blood?
* Most carbon dioxide is transported in the plasma as bicarbonate ion (HCO3−)
* A small amount is carried inside red blood cells on hemoglobin, but at different binding sites from those of oxygen
82
Concept Link 3
Remember that blood p H should remain between 7.35 and 7.45 (Chapter 10, p. 338). Buffers, such as bicarbonate ion, minimize changes in p H in order to maintain homeostasis.
83
For carbon dioxide to diffuse out of blood into the alveoli, it must be released from its:
* Bicarbonate form
* Bicarbonate ions enter RBC
* Combine with hydrogen ions
* Form carbonic acid (H2CO3)
* Carbonic acid splits to form water + CO2
* Carbon dioxide diffuses from blood into alveoli
84
Internal respiration is an _____ reaction from what occurs in the lungs.
* Opposite
* Carbon dioxide diffuses out of tissue cells to blood (called loading)
* Oxygen diffuses from blood into tissue (called unloading)
85
What is neural regulation?
Setting the basic rhythm
86
Activity of respiratory muscles is transmitted to and from the brain by _____ and _____ nerves.
* Phrenic
| * Intercostal
87
Neural centers that control rate and depth of respiration are located in the _____ and _____.
* Medulla—sets basic rhythm of breathing and contains a pacemaker (self-exciting inspiratory center) called the ventral respiratory group (VRG)
* Pons—smoothes out respiratory rate
88
What is eupnea?
* Normal respiratory rate
| * 12 to 15 respirations per minute
89
What is hyperpnea?
Increased respiratory rate, often due to extra oxygen needs
90
What non-neural factors influence respiratory rate and depth?
* Physical factors such as increased body temperature, exercise, talking, and coughing
* Volition (conscious control)
* Emotional factors such as fear, anger, and excitement
* Chemical factors such as CO2 levels, oxygen levels, hyperventilation, and hypoventilation
91
How do CO2 levels influence rate and depth of respiration?
* The body’s need to rid itself of C O2 is the most important stimulus for breathing
* Increased levels of carbon dioxide (and thus, a decreased or acidic p H) in the blood increase the rate and depth of breathing
* Changes in carbon dioxide act directly on the medulla oblongata
92
How do oxygen levels influence rate and depth of respiration?
* Changes in oxygen concentration in the blood are detected by chemoreceptors in the aorta and common carotid artery
* Information is sent to the medulla
* Oxygen is the stimulus for those whose systems have become accustomed to high levels of carbon dioxide as a result of disease
93
What is hyperventilation and how does it influence rate and depth of respiration?
* Rising levels of C O2 in the blood (acidosis) result in faster, deeper breathing
* Exhale more C O2 to elevate blood p H
* May result in apnea and dizziness and lead to alkalosis
94
What is hypoventilation and how does it influence rate and depth of respiration?
* Results when blood becomes alkaline (alkalosis)
* Extremely slow or shallow breathing
* Allows CO2 to accumulate in the blood
95
Chronic obstructive pulmonary disease (COPD) is exemplified by:
Chronic bronchitis and emphysema
96
Shared features of chronic bronchitis and emphysema include:
1. Patients almost always have a history of smoking
2. Labored breathing (dyspnea) becomes progressively worse
3. Coughing and frequent pulmonary infections are common
4. Most COPD patients are hypoxic, retain carbon dioxide and have respiratory acidosis, and ultimately develop respiratory failure
97
What is chronic bronchitis?
* Mucosa of the lower respiratory passages becomes severely inflamed
* Excessive mucus production impairs ventilation and gas exchange
* Patients become cyanotic and are sometimes called “blue bloaters” as a result of chronic hypoxia and carbon dioxide retention
98
What is emphysema?
* Alveoli walls are destroyed; remaining alveoli enlarge
* Chronic inflammation promotes lung fibrosis, and lungs lose elasticity
* Patients use a large amount of energy to exhale; some air remains in the lungs
* Sufferers are often called “pink puffers” because oxygen exchange is efficient
* Over-inflation of the lungs leads to a permanently expanded barrel chest
* Cyanosis appears late in the disease
99
What is lung cancer?
* Leading cause of cancer death for men and women
* Nearly 90 percent of cases result from smoking
* Aggressive cancer that metastasizes rapidly
100
What are the three common types of lung cancer?
* Adenocarcinoma
* Squamous cell carcinoma
* Small cell carcinoma
101
Lungs do not fully inflate until __ weeks after birth.
* 2
* This change from nonfunctional to functional respiration depends on surfactant
* Surfactant lowers surface tension so the alveoli do not collapse
* Surfactant is formed late in pregnancy, around 28 to 30 weeks
102
How do respiratory rate changes throughout life?
* Newborns: 40 to 80 respirations per minute
* Infants: 30 respirations per minute
* Age 5: 25 respirations per minute
* Adults: 12 to 18 respirations per minute
* Rate often increases again in old age
103
What is asthma?
* Chronically inflamed, hypersensitive bronchiole passages
| * Respond to irritants with dyspnea, coughing, and wheezing
104
Most respiratory system problems in youth and those middle aged are a result of external factors, such as _____ and substances that _____ respiratory passageways
* Infections
| * Physically block
105
What are aging effects of the respiratory system?
* Elasticity of lungs decreases
* Vital capacity decreases
* Blood oxygen levels decrease
* Stimulating effects of carbon dioxide decrease
* Elderly are often hypoxic and exhibit sleep apnea
* More risks of respiratory tract infection
