Respiratory system: Exam #2 review Flashcards
Everything below the trachea is _______
Sterile
- ) Name the structures of the conducting zone (7)
2. ) What is their purpose?
- ) Nose, nasopharynx, larynx, trachea, bronchi, bronchioles, terminal bronchioles
- ) Bring air in and out of the respiratory zone for gas exchange, and to warm, humidify, and filter air before it reaches the gas exchange region.
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The conducting airways are lined with ______ and ______ that function to _______.
Lined with mucus-secreting and ciliated cells that function to remove inhaled particles.
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What are the effects on the smooth muscles of the airways by (and what are their receptors and what are they activated by?)…
- ) Sympathetic innervation
- ) Parasympathetic innervation
1.) Sympathetic adrenergic neurons activate ß2 receptors on bronchial smooth muscle, which leads to RELAXATION and DILATION of the airways. Activated by circulating epinephrine released from the adrenal medulla AND by ß2-adrenergic agonists such as ISOPROTERENOL, EPINEPHRINE, and ALBUTEROL.
- ) Parasympathetic cholinergic neurons activate MUSCARINIC RECEPTORS, which leads to CONTRACTION and CONSTRICTION of the airways
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- ) What drugs are used to treat asthma?
- ) What do they target?
- ) What is their effect?
- ) ß2-adrenergic agonists (e.g. EPINEPHRINE, ISOPROTERENOL, ALBUTEROL)
- ) ß2-adrenergic receptors (sympathetic)
- ) Dilation of airways
p. 186
Name and describe the structures of the respiratory zone, i.e. participate in gas exchange (3)
- ) Respiratory bronchioles: Transitional structures with cilia, smooth muscle, and occasionally budding ALVEOLI (for gas exchange).
- ) Alveolar ducts: Completely lined with alveoli. No cilia, little smooth muscle. Terminate in the… –>
- ) Alveolar sacs: Also lined with alveoli.
p. 186
Each lung has a total of approx. ______ alveoli
300 million
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Alveoli exchange ____ and _____ between _____ and ______.
O2 and CO2 between alveolar gas and pulmonary capillary blood.
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Alveolar walls are rimmed with ______, and lined with _____ (called _____ and ______).
Rimmed with elastic fibers.
Lined with epithelial cells called TYPE I and TYPE II PNEUMOCYTES (or alveolar cells).
p.186
What are the functions of TYPE II pneumocytes (2)? What is their main purpose?
They regenerative capacity for type I and II pneumocytes.
- **MOST IMPORTANTLY, they synthesize PULMONARY SURFACTANT, which is necessary for the reduction of surface tension of alveoli so they don’t collapse.
p. 187
Alveoli contain phagocytic cells called ______. What do they do?
ALVEOLAR MACROPHAGES, which keep the alveoli free of dust and debris because ALVEOLI HAVE NO CILIA TO PERFORM THIS FUNCTION.
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Alveolar macrophages fill with debris and migrate to the _____. Why?
Migrate to the BRONCHIOLES, where beating cilia carry debris to the UPPER AIRWAYS and PHARYNX where it can be swallowed or expectorated.
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- ) The _____ is the main conducting airway.
- ) Explain its divisions, i.e. how it divides/what it divides into.
- ) Ultimately, how many divisions into smaller airways are there?
- ) Trachea
- ) It divides into two bronchi, one leading to each lung, which divide into two smaller bronchi, which divide again.
- ) 23 such divisions
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Which structures of the conducting/respiratory tract have cartilage?
Trachea, bronchi (some, patchy). THAT’S IT!!!
p.186
Changes in pulmonary arteriolar resistance are controlled by ______, mainly ______.
Controlled by local factors, mainly O2.
p.187
Because of ______, pulmonary blood is not evenly distributed in the lungs. Explain.
Gravitational forces. When a person is standing, blood flow is lowest AT THE APEX (top) of the lungs, and highest AT THE BASE (bottom) of the lungs. When a person is supine, THESE GRAVITATIONAL EFFECTS DISAPPEAR.
p.187
Regulation of pulmonary blood flow is accomplished by _______
Altering the resistance of the PULMONARY ARTERIES.
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- ) _______ is the blood supply to the conducting airways.
2. ) It is a [large or small?] fraction of the total pulmonary blood flow
- ) Bronchial circulation
- ) VERY SMALL FRACTION
p. 187
_____ volumes of the lung are measured with a spirometer.
Static
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What is tidal volume (Vt). What is the normal value for tidal volume?
Tidal volume (Vt) is the volume of air that fills the alveoli PLUS the volume that fills the airways.
- Normal tidal volume is approx. 500 mL.
p. 187
What is the term for the additional volume that can be inspired ABOVE tidal volume? What is the normal value for this?
Inspiratory reserve volume (IRV).
Normal value is approx. 3000 mL.
p.187
What is the term for the additional volume that can be expired BELOW tidal volume? What is the normal value for this?
Expiratory reserve volume (ERV).
Normal value is approx. 1200 mL.
p.187
What is the term for the volume of gas remaining in the lungs after maximal forced expiration? What is the normal volume recorded by spirometry?
Residual volume (RV).
Normal value is approx. 1200 mL and CANNOT BE MEASURED BY SPIROMETRY.
p.187
Define the four different types of lung capacity…
a. ) What their volumes are composed of, and…
b. ) What their normal values are (e.g. n = #1 + #2)
- ) Inspiratory capacity (IC):
a. ) Composed of TIDAL VOLUME plus the INSPIRATORY RESERVE VOLUME.
b. ) Normal value is approx. 3500 mL (500 mL + 3000 mL). - ) Functional residual capacity (FRC): The volume remaining in the lungs after normal tidal volume is expired (*can be thought of as the EQUILIBRIUM VOLUME).
a. ) Composed of EXPIRATORY RESERVE VOLUME (ERV) plus the RESIDUAL VOLUME.
b. ) Normal value is approx. 2400 mL (1200 mL + 1200 mL). - ) Vital capacity (VC): The volume that can be expired after MAXIMAL INSPIRATION.
a. ) Composed of INSPIRATORY CAPACITY plus the EXPIRATORY RESERVE VOLUME.
b. ) Normal value is approx. 4700 mL (3500 mL + 1200 mL). - ) Total lung capacity (TLC): Includes ALL LUNG VOLUMES.
a. ) It is composed of the vital capacity plus the residual volume.
b. ) Normal value is approx. 5900 mL (4700 mL + 1200 mL).
p.187