Chapter 22: Respiratory System Anatomy Flashcards
(123 cards)
1
Q
Upper respiratory tract
A
consists of the nose, pharynx
2
Q
Lower respiratory tract
A
consists of the larynx, trachea, bronchi and lungs
3
Q
Conducting zone
A
**move air in and out of lungs
**warms, cleans, moistens air
**bringing air to the site of external respiration
**consists of the nose, pharynx, larynx, trachea, bronchi, bronchioles and terminal bronchioles
4
Q
Respiratory zone
A
**gas exchange
**consists of the respiratory bronchioles, alveolar ducts, alveolar sacs, and alveoli.
5
Q
Much, not all, of the respiratory tract is covered with __________________________________________________________ with interspersed ______ cells (secrete mucous)
A
pseudostratified ciliated columnar epithelium
goblet
6
Q
Cilia in the upper respiratory tract move secreted mucous with trapped particles down toward the _________.
Cilia in the lower respiratory tract move secreted mucous up toward the _________.
A
pharynx
larynx
7
Q
the only place in the nervous system where neurons can be replaced if damaged
A
olfactory nerves in olfactory mucosa
8
Q
INTERNAL NOSE
What divides the internal nasal cavity into right and left nares?
A
nasal septum
9
Q
INTERNAL NOSE
**opening under nasal conchae that protrude from each lateral wall into the breathing passages
**for a duct that drains secretions of the sinuses and tears into the nose
A
meatus
10
Q
INTERNAL NOSE
Receptors in the ______________________ (used for smell) pierce the bone of the __________________.
A
olfactory epithelium
cribriform plate
11
Q
Functions of the Nasal Mucosa and Conchae
A
During inhalation, conchae and nasal mucosa
Filter, heat, and moisten air
During exhalation these structures
Reclaim heat and moisture
12
Q
External nose contains nasal hair in nostril cavities to…?
A
Help filter air entering the nasal passage and may help reclaim some moisture from exhaled air
13
Q
**a passageway for air and food
**a resonating chamber for sound
**a housing for the tonsils (lymphatic organs)
A
pharynx
14
Q
The nasopharynx lies behind the internal nares.
It contains the openings of the ___________________ (auditory tubes), which come off of it, and travels to the ___________ cavity.
A
Eustachian tubes
middle ear
15
Q
The oropharynx lies behind the mouth and participates in both ___________ and __________ functions.
A
respiratory
digestive
16
Q
The laryngopharynx lies inferiorly and opens into the larynx (voice box) and the esophagus.
A
larynx
esophagus
17
Q
As air passes from the laryngopharynx into the _______, it leaves the upper respiratory tract and enters the lower respiratory tract.
A
larynx
18
Q
composed of 9 pieces of cartilage, forms a short passageway connecting the laryngopharynx with the trachea (the “windpipe”).
A
larynx
19
Q
**a flap of elastic cartilage located in larynx covered with a mucus membrane
**guards glottis entrance
**blocking food or liquid from entering the airway
A
epiglottis
20
Q
What happens to the epiglottis when breathing?
A
It is held anteriorly to uncover glottic opening
21
Q
glottic opening –> is formed by a pair of mucous membrane vocal folds (the true vocal cords; produce sound)
A
rima glottidis
22
Q
The ____________ are situated high in the larynx just below where the larynx and the esophagus split off from the pharynx.
A
vocal folds
23
Q
a semi-rigid pipe made of semi-circular cartilaginous rings (hyaline cartilage), and located anterior to the esophagus.
A
trachea
24
Q
trachea extends from the inferior portion of the larynx into the _____________ where it divides into right and left primary (1o, “mainstem”) bronchi.
A
mediastinum
25
The tracheal cartilage rings are incomplete ____________, facing the _____________.
posteriorly
esophagus
**This allows the esophagus to expand as it moves the bolus of swallowed food toward the stomach
26
The right and left primary (1o or “mainstem”) bronchi emerge from the inferior ______ to go to the lungs, situated in the right and left pleural cavities.
trachea
27
**internal ridge located at the junction of the two mainstem (primary) bronchi
**can trigger cough reflex
carina
28
Tertiary bronchi divide into _____________ which in turn branch through about 22 more divisions.
bronchioles
29
connects adjacent alveoli
Pores of Kohn
30
__________ bronchiole (conducting) goes into ____________ bronchiole.
Terminal
respiratory
31
______________ help to recoil after expiration.
**Those don’t work well in emphysema
Elastic fibers
32
As organs, the lungs are divided into lobes by ________.
How many lobes do the right and left lungs have?
fissures
right lung --> 3 lobes
left lung --> 2 lobes
33
The ________________ – in the left lung (the indentation for the heart) makes the left lung ___ % smaller than the right lung.
cardiac notch
10%
34
The lungs are separated from each other by the heart and other structures in the _________________.
mediastinum
35
Each lung is enclosed by ....
....a sealed double-layered pleural membrane.
36
The _________ pleura line the walls of the thoracic cavity.
The _________ pleura adhere tightly to the surface of the lungs themselves.
Pleural fluid, secreted by the pleural membrane, reduces friction so the layers can slide across one another.
parietal
visceral
37
The pleura, adherent to the chest wall and to the lung, produces a _________________________ for the two layers to move together.
mechanical coupling
38
Bronchi + bronchioles structural changes with branching and becoming smaller...
As the amount of cartilage rings __________, smooth muscle content (under the control of the Autonomic Nervous System) ___________.
decrease
increase
39
Sympathetic stimulation causes airway _________ → bigger airway = less airflow resistance
dilation
40
Parasympathetic stimulation causes airway ____________ → smaller airway = more airflow resistance.
constriction
41
All the branches from the trachea to the terminal bronchioles are ___________ airways
Do they participate in gas exchange?
conducting
No!
42
**at end of bronchiole branching, cup-shaped outpouchings begin to occur
**participate in gas exchange
alveoli
43
**Respiratory bronchioles give way to alveolar ducts
**Here, the epithelium (_________________) changes to ___________________, which comprises the alveolar ducts, alveolar sacs, and alveoli.
simple cuboidal
simple squamous
44
Terminal bronchioles
Respiratory bronchioles
Alveolar ducts and alveoli
Capillaries
Elastic fibers
Lymphatic vessels
Blood vessels
All these form the functional unit of the lung...
pulmonary lobule
45
alveoli are delicate structures composed chiefly of _____________ cells, which allow for exchange of gases with the pulmonary capillaries.
type I alveolar
46
Type II alveolar cells secrete a substance called __________ that decreases surface tension and prevents collapse of the alveoli during exhalation.
They also can give rise to ______ cells.
surfactant
type I
47
Alveolar fluid's water surface tension is due to the strong attraction between water molecules at the surface of a liquid, which draws the water molecules closer together.
What lowers this tension?
Surfactant is a mixture of phospholipids and lipoproteins which lowers the surface tension of the alveolar fluid
Without surfactant, alveoli would have to be completely reinflated between breaths
48
**alveolar capillaries are closely associated with the alveolar lumen
**where air and blood meet in the lungs
**O2 and CO2 easily pass through thin wall for gas exchange
Air blood barrier
49
_______________________ (also called “_________”) scavenge the alveolar surface to engulf and remove microscopic debris that has made it past the “mucociliary blanket” that traps most foreign particles higher in the respiratory tract.
Alveoli macrophages
"dust cells"
50
The alveoli in close proximity to the capillaries form the __________________________ (“AC membrane”).
alveolar-capillary membrane
aka respiratory membrane
51
in many regions of respiratory (AC) membrane, there is no _________________
interstitial fluid
52
why is the respiratory (AC) membrane thin?
Oxygen and carbon dioxide can diffuse easily
53
Type 1 alveolar are what type of tissue?
simple squamous epithelial tissue
54
The lungs receive blood via two sets of arteries...
pulmonary arteries
bronchial arteries
55
Bronchial arteries branch from the ______ and deliver oxygenated blood to the lungs, primarily ______________________ of the bronchi and bronchioles
aorta
perfusing the muscular walls
56
Carries deoxygenated blood into the lungs alongside the bronchi, branching to form alveolar capillary networks at the respiratory bronchioles. It has thinner walls with more elastic fibers and less smooth muscle than systemic arteries, and functions under lower pressure (≈25/8 mm Hg vs. 120 mm Hg systolic in systemic arteries).
Pulmonary artery
57
Carries oxygenated blood to the walls of the bronchi, vessels, and connective tissue. Its branches follow the bronchial tree, and its capillaries connect (anastomose) with pulmonary vein and bronchial vein plexuses.
Bronchial artery
58
Located around bronchi, bronchioles, vessels, and alveolar septa; connects to the superficial plexus and drains into the hilum and main lymphatic vessels.
Deep (pulmonary) lymphatic plexus
59
veins that drain the alveolar capillaries
Pulmonary vein plexuses
60
Vein that transports oxygenated blood back to the heart. It arises from venules draining the alveolar capillary plexuses and travels in the connective tissue septa.
Pulmonary vein
61
the coupling of perfusion (blood flow) to each area of the lungs to match the extent of ventilation (airflow) to alveoli in that area
Ventilation-perfusion coupling
62
In the lungs, ______________ in response to hypoxia diverts pulmonary blood from poorly ventilated areas of the lungs to well-ventilated regions
In all other body tissues, hypoxia causes _________ of blood vessels to increase blood flow
vasoconstriction
dilation
63
Conducting zone bronchi --> bronchioles changes
cartilage rings --> irregular plates
cartilage --> elastic fibers
pseudostratified columnar --> cuboidal
cilia + goblet cells sparse
smooth muscle increases
64
what are the respiratory zone structures?
respiratory bronchioles, alveolar ducts, alveolar sacs (saccules) (site of gas exchange)
65
The visceral and parietal pleurae are actually a _____________ of the _____ membrane
continuation ; same
The relationship between the pleurae and the lungs can be demonstrated by pushing a fist into a water-filled balloon
66
boundary of visceral pleura
lungs
67
boundary of parietal pleura
mediastinum, diaphragm, thoracic wall
68
The trachea and bronchi have supporting ___________ to keep airways open
cartilage
69
what is respiration and what are the 3 basic steps?
process of gas exchange in the body
Pulmonary ventilation
External (pulmonary) respiration
Internal (tissue) respiration
70
pulmonary ventilation phases
Inspiration: gases flow into lungs
Expiration: gases exit lungs
71
how is ventilation made possible?
changes in pressure at the alveoli relative to the atmospheric pressure
changes in P due to changes in thoracic volume
72
mechanical coupling between .... results in breathing
the lungs, the pleural cavities, and the chest wall
73
prior to normal inspiration, atm and alveolar P are _____
equal
74
during inspiration, how is the volume of the thoracic cavity increased
diaphragm contraction (flattens) --> thoracic cavity length increases
external intercostals contractions --> elevate ribs --> increase width
lungs and visceral pleura pulled outwards, resulting in increased lung volume
75
air moves into lungs when air P ________ alveolar P
exceeds
76
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
Atmospheric pressure (P atm)
Pressure exerted by air surrounding the body
760 mm Hg at sea level = 1 atmosphere
77
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
Negative respiratory pressure:
Positive respiratory pressure:
Zero respiratory pressure:
Negative respiratory pressure: less than P atm
Positive respiratory pressure: greater than P atm
Zero respiratory pressure: equal to P atm
78
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
Intrapulmonary pressure (P pul)
Pressure in alveoli
Also called intra-alveolar pressure
Fluctuates with breathing
Always eventually equalizes with P atm --> 760 mm Hg
79
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
Intrapleural pressure (P ip)
Pressure in pleural cavity
Fluctuates with breathing
Always a negative pressure ( 756 mm Hg
80
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
fluid level in pleural cavity must be kept at a minimum
what happens when fluid accumulation occurs?
Intrapleural pressure (P ip) becomes positive
LUNG COLLAPSES
81
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
what two inward forces promote lung collapse?
1. Lungs’ natural tendency to recoil --> elasticity
2. Surface tension of alveolar fluid --> pulls alveoli to reduce its size
82
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
what outward force expands lungs?
Elasticity of chest wall pulls thorax outward
83
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
Negative Pip is affected by opposing forces but is maintained by _______________________ between parietal and visceral pleurae
strong adhesive force
84
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
Transpulmonary pressure = (Ppul − Pip)
the differences between 0 mm Hg and -4 mm Hg
Pressure that keeps lung spaces open
Keeps lungs from collapsing
85
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
greater transpulmonary pressure means ...
the larger the lungs will be
86
PRESSURE RELATIONSHIPS IN THE THORACIC CAVITY
lungs will collapse if...
Pip = Ppul or
Pip = Patm
Negative P ip must be maintained to keep lungs inflated
87
PRESSURES INVOLVED IN VENTILATION
Intrapulmonary (intra-alveolar) pressure (P pul)
Pressure in alveoli
Changes when breathing
Always eventually equalizes with Patm
88
PRESSURES INVOLVED IN VENTILATION
Intrapleural pressure (P ip)
Changes when breathing
This should always be a negative pressure (
89
what happens when there is accumulation of plural fluid in pleural cavity in terms of pressure?
Plural fluid helps limit friction between lungs and thoracic wall, but fluid amount must be kept to a minimum
Excess is pumped out by lymphatics
If accumulates → positive P ip pressure → lung collapse
90
during inspiration, air flows from ____ pressure to ____ pressure
high
low
91
For air to flow into the lungs, the pressure in the alveoli must be _____ than atmospheric
less
92
This decrease in alveoli pressure is accomplished by ____________ the volume of the lungs through mechanical coupling to a change in thoracic volume
increasing
93
diaphragm innervated by the ________ nerve
phrenic
94
what is responsible for about 75% of air that enters the lungs during resting (quiet) breathing?
Patm > internal alveoli P --> causes lungs to fill with air --> equalizes the 2 P's
95
what is responsible for ~25% of the air entering the lungs during quiet breathing?
external intercostals --> elevates ribs --> increases anteroposterior and lateral diameters of chest cavity
96
muscles involved in active inhalation --> increasing thoracic volume during exercise/deep inhales
Accessory muscles of inhalation
sternocleidomastoid
scaline
pectoralis minor
97
during expirarion, The pressure in the lungs is ________ than that of the atmosphere
greater
98
Normal exhalation during quiet breathing with no muscular contractions are involved
passive exhalation
99
passive exhalation results from inward forces such as...
The elastic recoil of the chest wall and lungs
the inward pull of the surface tension of the alveolar fluid
100
Exhalation begins when the inspiratory muscles ______
relax
101
when diaphragm and external intercostals relax during passive exhalation:
it __________ lung volume
causes an __________ in alveolar pressure ______ that of atmospheric
decreases
increase
above
**Air flows from high (lungs) to low (external environment) pressure
102
Forceful exhalation
Yelling, exercise, or playing a wind instrument
Requires muscles of exhalation
Active exhalation
103
ACTIVE EXHALATION
Muscle moves the inferior ribs downward and compresses the abdominal viscera
Forces the diaphragm superiorly
Abdominals
104
ACTIVE EXHALATION
Pulls the ribs inferiorly (downward)
Internal intercostals
105
**air, or liquid (blood or Interstitial fluid), in pleural cavity
**From either wound in parietal or rupture of visceral pleura
Pneumothorax
106
during a pneumothorax, intrapleural pressure goes from -4 to __ thus eliminating the transpulmonary pressure that keeps a lung open
what happens to lung?
0
Inward forces no longer opposed by outward force --> lung collapses in on itself
107
Differences in air pressure drive airflow, but 3 other factors also affect the ease with which we ventilate:
The surface tension of alveolar fluid
Compliance of the lungs
Airway resistance
108
The surface tension of alveolar fluid is found at all __________ interfaces
air-water
109
Deficiency of surfactant in premature infants
Treated by using continuous positive air pressure (CPAP) breathing machines - increases pressure of air going into the lungs - and synthetic surfactant until infant begins producing its own
Infant Respiratory Distress Syndrome (IRDS)
110
How easily something stretches, like lung expansion
compliance
111
Lung compliance dependent upon 2 factors
elasticity
surface tension
112
factors decreasing complaince
Restrictive disorders restrict lung expansion resulting in a decreased lung volume
Pulmonary fibrosis
Deposition of scar tissue in the lungs
Scar tissue not very elastic
Deficiency in surfactant
Pulmonary edema (excess fluid in the lungs)
Decreases lung compliance
Impedance to expansion
E.g. Ventilatory muscle paralysis, broken ribs, obesity
113
Smooth muscle’s role in airway resistance
The diameter of airways is regulated by smooth muscle tone which, as previously discussed, is dependent upon parasympathetic and sympathetic interaction
114
Any condition that narrows, or obstructs, the airways ____________ resistance
increases
115
Any pathological condition that narrows, or obstructs, airways
Obstructive disorders
116
Types of obstructive lung disease include
asthma, bronchitis, chronic obstructive pulmonary disease (COPD), emphysema, cystic fibrosis, etc.
117
__% of the tidal volume (air breathed in and out at rest) reaches the respiratory zone
70
118
70% of the tidal volume (air breathed in and out at rest) reaches the respiratory zone – the other 30% remains in the conducting zone (called the ______________________, no contribution to gas exchange).
anatomical dead space
119
non-functional alveoli due to collapse, poor perfusion, or obstruction
Alveolar dead space
120
sum of anatomical and alveolar dead space
Physiological (total) dead space
121
amount of air moved into and out of lung with each breath
Averages ~500ml
Tidal volume (TV)
122
amount of air that can be inspired forcibly beyond the tidal volume (2100–3200 ml)
Inspiratory reserve volume (IRV)
123
amount of air that can be forcibly expelled from lungs (1000–1200 ml)
Expiratory reserve volume (ERV)
