Respiratory Anatomy and Physiology-
Questions and Answers Graded A+
What does the respiratory system do? - ANSWER-2 main things:
Ventilation - Breathing or Respiration - prerequisite for: Gas Exchange
What are the muscles of inspiration? - ANSWER-Diaphragm
External Intercostals
What are muscles of expiration? - ANSWER-Internal Intercostals
Abdominal Muscles
What does the diaphragm do? - ANSWER-When the dome-shaped diaphragm contracts, it is pulled
inferiorly into the abdomen and subsequently "flattens out". As a result, the vertical dimension of the
thoracic cavity increases.
Which branches of the phrenic nerve innervate the diaphragm? - ANSWER-C3-C5 - cervical - keep
the diap
hragm alive!
What happens when the external intercostals contract? - ANSWER-They do two things:
elevate the ribs superolaterally - "bucket handle"
move the sternum anteriorly - "pump handle"
As a result, the transverse and anteroposterior dimensions of the thoracic cavity are increased.
What are characteristics of inhalation? - ANSWER-active process
inspiratory muscles
phrenic nerve
What are characteristics of exhalation? - ANSWER-passive process - quiet
elastic recoil
active process - forced
Where are the lobes of the lung? - ANSWER-Lower lobes are posterior
What happens when the internal intercostals contract during expiration? - ANSWER-They depress
the ribcage and decrease thoracic volume
What happens when the internal abdominal muscles contract during expiration? - ANSWER-When
the internal abdominal muscles contract, they raise the intra-abdominal pressure, which forces the
abdominal viscera superiorly against the diaphragm
What are the upper respiratory structures? - ANSWER-nose
pharynx
larynx
What are the lower respiratory structures? - ANSWER-trachea
bronchi
bronchioles
alveolar ducts & sacs
,alveoli
What are the jobs of the conduction zone? - ANSWER-moves air
warms air
moistens air
filters air
airway resistance
What is the job of the respiratory zone? - ANSWER-gas exchange
How does the bronchial tree function to provide gas exchange? - ANSWER-The airways channel air
from the external atmosphere to the blood-gas interface. The airways begin with the trachea
(generation 0) and then branch repeatedly to yield a bronchial tree. The tree contains approx. 23
branch generations and comprises two functionally distinct zones.
How do the structures of the conduction zone and respiratory zone compare? - ANSWER-
How is airway resistance in the bronchi and bronchioles overcome? - ANSWER-The greatest site of
airway resistance occurs within the bronchi & bronchioles - where there is LOTS of smooth muscle -
they are affected by the sympathetic nervous system via b2 receptors -bronchodilation & the
parasympathetic nervous system via muscarinic receptors -
bronchoconstriction
What are characteristics of alveoli? - ANSWER-Overwhelming majority of gas exchange occurs
within the alveoli -- smaller amount occurs with respiratory bronchioles
Alveoli are richly surrounded by pulmonary capillaries
Each lung has a total of approx. 300 million alveoli
What lines the trachea down to the non-respiratory bronchioles? - ANSWER-Respiratory epithelium
or mucosa - pseudo stratified columnar epithelium - components are basilar membrane, goblet cells,
cilia
What is a pneumothorax? - ANSWER-The presence of air in the intrapleural space on one side of
the chest...........which leads to COLLAPSE!
What are the components of the lung pleurae? - ANSWER-Parietal Pleura
Visceral Pleura
Pleural Fluid
What are characteristics of the pleural fluid? - ANSWER-Normally, the intrapleural space contains
just enough fluid to make both portions of the pleura moist & slippery and able to glide easily against
each other as the lungs expand and deflate with each breath.
Are the alveoli ever completely devoid of air? - ANSWER-No - the lungs are always in a partial state
of inflation to make inhalation easier, even though lungs want to recoil.
What can affect the pleural space? - ANSWER-Infection, trauma can cause swelling/effusion, which
puts pressure on the lung
,What is significant about the alveolar-pulmonary capillary inerface? - ANSWER-Physiological
significance lies with the interface's THINNESS & small amount of interstitial fluid. Notice the 0.2
distance in the photo.
What are characteristics of the Type I alveolar cell - type I pneumocyte? - ANSWER-are thin and flat
(simple squamous); constitute 90% of alveolar surface area
What are the characteristics of the Type II alveloar cell -
Type II pneumocyte? - ANSWER-synthesize pulmonary surfactant
What is the job of an alveolar macrophage - dust cell? - ANSWER-clean off particles such as dust or
microorganisms; frequently contain granules of exogenous material such as particulate carbon that
they have picked up from respiratory surfaces - particularly in smokers
What is the importance of alpha-1 antitrypsin? - ANSWER-The lungs are mainly airways surrounded
by elastic tissue - containing the protein ELASTIN
Neutrophils can secrete ELASTASE when cleaning up cellular debris as a result of inflammation
ALPHA-1-ANTITRYPSIN protects tissues from neutrophil elastase
The absence of alpha-1-antitrypsin results in respiratory complications - emphysema, COPD and
cirrhosis
An absence of this enzyme can cause COPD even without smoking!
What is spirometry? - ANSWER-Diagnostic spirometry is a tool for the measurement of the breathing
capacity of the lungs
How does spirometry help? - ANSWER-distinguish between different types of lung diseases
determine the severity of functional impairment
monitor the treatment of a lung disorder
Plots a tracing - the spirogram - of the lung volume against time - in seconds
What is incentive spirometry? - ANSWER-Incentive spirometry is a method of encouraging voluntary
deep breathing by providing visual feedback about inspiratory volume.
Using a specially designed spirometer, the patient inhales until a preset volume is reached, then
sustains the inspiratory volume by holding his or her breath for 3 to 5 seconds.
Incentive spirometry reduces the risk of atelectasis and pulmonary consolidation.
What is tidal volume? - ANSWER-The amount of air that moves into and out of the (TV) airways with
each inspiration and expiration during normal quiet breathing -- usually around 500 ml
How do you calculate minute volume? - ANSWER-Total volume of air taken in by the body during 1
minute
MVe = TV x RR (RR=respiratory rate)
What is anatomical dead space? - ANSWER-The portion of the tidal volume that remains in the
nose, pharynx, larynx, trachea, bronchi, and terminal bronchioles -- i.e. the air that does not
participate in gas exchange
What is alveolar ventilation, and how is it calculated? - ANSWER-Total volume of air that reaches
the sites of gas exchange during 1 minute AVe = (TV-ADS) x RR
, What is inspiratory reserve volume - IRV? - ANSWER-The amount of air you can inspire above your
normal tidal volume
What is expiratory reserve volume - ERV? - ANSWER-The amount of air you can expire above your
normal tidal volume
What is Residual Volume - RV? - ANSWER-The amount of air that remains in the respiratory system
after a forced expiration
What is Functional Residual Capacity - FRC? - ANSWER-The sum of the residual volume and
expiratory reserve volume
Amount of air remaining in lungs after normal respiration
What is inspiratory capacity - IC? - ANSWER-The sum of the tidal volume and IRV
What is vital capacity? - ANSWER-The sum of tidal volume, IRV and ERV
What are pressures involved with breathing? - ANSWER-Atmospheric Pressure
Intra-Alveolar Pressure - Intrapulmonary Pressure - pressure in the lungs
Intrapleural Pressure - pressure in pleural cavity
Transpulmonary Pressure - the difference in pressure between intra-alveolar pressure and
intrapleural pressure
How is negative intrapleural pressure established? - ANSWER-The answer lies in the forces that
exist within the thoracic cavity. Two forces act to pull the lungs (visceral pleura) away from the chest
wall (parietal pleura) and cause lung collapse:
1. The lungs' natural tendency to recoil. Because of their elasticity, lungs always assume the
smallest size possible.
2. The surface tension of the alveolar fluid constantly acts to draw the alveoli to their smallest
possible dimension.
What opposes the lung-collapsing forces? - ANSWER-The natural elasticity of the chest wall, a force
that tends to pull the thorax outward and to enlarge the lungs. So which force wins? The answer is
neither in a healthy person, because of the strong adhesive force between the parietal and visceral
pleura. Pleural fluid secures the pleurae together in the same way a drop of water holds two glass
slides together. The pleurae slide from side to side easily, but they remain closely apposed, and
separating them requires extreme force. The net result of the dynamic interplay between these
forces is a negative Pip.
What are the implications of Boyle's Law? - ANSWER-P1V1 = P2V2
Volume changes lead to pressure changes, and pressure changes lead to the flow of gases to
equalize the pressure
What are the characteristics of the respiratory cycle at rest? - ANSWER-Alveolar pressure equals
atmospheric pressure
Because lung pressures are expressed relative to atmospheric pressure, alveolar pressure is said to
be zero
Questions and Answers Graded A+
What does the respiratory system do? - ANSWER-2 main things:
Ventilation - Breathing or Respiration - prerequisite for: Gas Exchange
What are the muscles of inspiration? - ANSWER-Diaphragm
External Intercostals
What are muscles of expiration? - ANSWER-Internal Intercostals
Abdominal Muscles
What does the diaphragm do? - ANSWER-When the dome-shaped diaphragm contracts, it is pulled
inferiorly into the abdomen and subsequently "flattens out". As a result, the vertical dimension of the
thoracic cavity increases.
Which branches of the phrenic nerve innervate the diaphragm? - ANSWER-C3-C5 - cervical - keep
the diap
hragm alive!
What happens when the external intercostals contract? - ANSWER-They do two things:
elevate the ribs superolaterally - "bucket handle"
move the sternum anteriorly - "pump handle"
As a result, the transverse and anteroposterior dimensions of the thoracic cavity are increased.
What are characteristics of inhalation? - ANSWER-active process
inspiratory muscles
phrenic nerve
What are characteristics of exhalation? - ANSWER-passive process - quiet
elastic recoil
active process - forced
Where are the lobes of the lung? - ANSWER-Lower lobes are posterior
What happens when the internal intercostals contract during expiration? - ANSWER-They depress
the ribcage and decrease thoracic volume
What happens when the internal abdominal muscles contract during expiration? - ANSWER-When
the internal abdominal muscles contract, they raise the intra-abdominal pressure, which forces the
abdominal viscera superiorly against the diaphragm
What are the upper respiratory structures? - ANSWER-nose
pharynx
larynx
What are the lower respiratory structures? - ANSWER-trachea
bronchi
bronchioles
alveolar ducts & sacs
,alveoli
What are the jobs of the conduction zone? - ANSWER-moves air
warms air
moistens air
filters air
airway resistance
What is the job of the respiratory zone? - ANSWER-gas exchange
How does the bronchial tree function to provide gas exchange? - ANSWER-The airways channel air
from the external atmosphere to the blood-gas interface. The airways begin with the trachea
(generation 0) and then branch repeatedly to yield a bronchial tree. The tree contains approx. 23
branch generations and comprises two functionally distinct zones.
How do the structures of the conduction zone and respiratory zone compare? - ANSWER-
How is airway resistance in the bronchi and bronchioles overcome? - ANSWER-The greatest site of
airway resistance occurs within the bronchi & bronchioles - where there is LOTS of smooth muscle -
they are affected by the sympathetic nervous system via b2 receptors -bronchodilation & the
parasympathetic nervous system via muscarinic receptors -
bronchoconstriction
What are characteristics of alveoli? - ANSWER-Overwhelming majority of gas exchange occurs
within the alveoli -- smaller amount occurs with respiratory bronchioles
Alveoli are richly surrounded by pulmonary capillaries
Each lung has a total of approx. 300 million alveoli
What lines the trachea down to the non-respiratory bronchioles? - ANSWER-Respiratory epithelium
or mucosa - pseudo stratified columnar epithelium - components are basilar membrane, goblet cells,
cilia
What is a pneumothorax? - ANSWER-The presence of air in the intrapleural space on one side of
the chest...........which leads to COLLAPSE!
What are the components of the lung pleurae? - ANSWER-Parietal Pleura
Visceral Pleura
Pleural Fluid
What are characteristics of the pleural fluid? - ANSWER-Normally, the intrapleural space contains
just enough fluid to make both portions of the pleura moist & slippery and able to glide easily against
each other as the lungs expand and deflate with each breath.
Are the alveoli ever completely devoid of air? - ANSWER-No - the lungs are always in a partial state
of inflation to make inhalation easier, even though lungs want to recoil.
What can affect the pleural space? - ANSWER-Infection, trauma can cause swelling/effusion, which
puts pressure on the lung
,What is significant about the alveolar-pulmonary capillary inerface? - ANSWER-Physiological
significance lies with the interface's THINNESS & small amount of interstitial fluid. Notice the 0.2
distance in the photo.
What are characteristics of the Type I alveolar cell - type I pneumocyte? - ANSWER-are thin and flat
(simple squamous); constitute 90% of alveolar surface area
What are the characteristics of the Type II alveloar cell -
Type II pneumocyte? - ANSWER-synthesize pulmonary surfactant
What is the job of an alveolar macrophage - dust cell? - ANSWER-clean off particles such as dust or
microorganisms; frequently contain granules of exogenous material such as particulate carbon that
they have picked up from respiratory surfaces - particularly in smokers
What is the importance of alpha-1 antitrypsin? - ANSWER-The lungs are mainly airways surrounded
by elastic tissue - containing the protein ELASTIN
Neutrophils can secrete ELASTASE when cleaning up cellular debris as a result of inflammation
ALPHA-1-ANTITRYPSIN protects tissues from neutrophil elastase
The absence of alpha-1-antitrypsin results in respiratory complications - emphysema, COPD and
cirrhosis
An absence of this enzyme can cause COPD even without smoking!
What is spirometry? - ANSWER-Diagnostic spirometry is a tool for the measurement of the breathing
capacity of the lungs
How does spirometry help? - ANSWER-distinguish between different types of lung diseases
determine the severity of functional impairment
monitor the treatment of a lung disorder
Plots a tracing - the spirogram - of the lung volume against time - in seconds
What is incentive spirometry? - ANSWER-Incentive spirometry is a method of encouraging voluntary
deep breathing by providing visual feedback about inspiratory volume.
Using a specially designed spirometer, the patient inhales until a preset volume is reached, then
sustains the inspiratory volume by holding his or her breath for 3 to 5 seconds.
Incentive spirometry reduces the risk of atelectasis and pulmonary consolidation.
What is tidal volume? - ANSWER-The amount of air that moves into and out of the (TV) airways with
each inspiration and expiration during normal quiet breathing -- usually around 500 ml
How do you calculate minute volume? - ANSWER-Total volume of air taken in by the body during 1
minute
MVe = TV x RR (RR=respiratory rate)
What is anatomical dead space? - ANSWER-The portion of the tidal volume that remains in the
nose, pharynx, larynx, trachea, bronchi, and terminal bronchioles -- i.e. the air that does not
participate in gas exchange
What is alveolar ventilation, and how is it calculated? - ANSWER-Total volume of air that reaches
the sites of gas exchange during 1 minute AVe = (TV-ADS) x RR
, What is inspiratory reserve volume - IRV? - ANSWER-The amount of air you can inspire above your
normal tidal volume
What is expiratory reserve volume - ERV? - ANSWER-The amount of air you can expire above your
normal tidal volume
What is Residual Volume - RV? - ANSWER-The amount of air that remains in the respiratory system
after a forced expiration
What is Functional Residual Capacity - FRC? - ANSWER-The sum of the residual volume and
expiratory reserve volume
Amount of air remaining in lungs after normal respiration
What is inspiratory capacity - IC? - ANSWER-The sum of the tidal volume and IRV
What is vital capacity? - ANSWER-The sum of tidal volume, IRV and ERV
What are pressures involved with breathing? - ANSWER-Atmospheric Pressure
Intra-Alveolar Pressure - Intrapulmonary Pressure - pressure in the lungs
Intrapleural Pressure - pressure in pleural cavity
Transpulmonary Pressure - the difference in pressure between intra-alveolar pressure and
intrapleural pressure
How is negative intrapleural pressure established? - ANSWER-The answer lies in the forces that
exist within the thoracic cavity. Two forces act to pull the lungs (visceral pleura) away from the chest
wall (parietal pleura) and cause lung collapse:
1. The lungs' natural tendency to recoil. Because of their elasticity, lungs always assume the
smallest size possible.
2. The surface tension of the alveolar fluid constantly acts to draw the alveoli to their smallest
possible dimension.
What opposes the lung-collapsing forces? - ANSWER-The natural elasticity of the chest wall, a force
that tends to pull the thorax outward and to enlarge the lungs. So which force wins? The answer is
neither in a healthy person, because of the strong adhesive force between the parietal and visceral
pleura. Pleural fluid secures the pleurae together in the same way a drop of water holds two glass
slides together. The pleurae slide from side to side easily, but they remain closely apposed, and
separating them requires extreme force. The net result of the dynamic interplay between these
forces is a negative Pip.
What are the implications of Boyle's Law? - ANSWER-P1V1 = P2V2
Volume changes lead to pressure changes, and pressure changes lead to the flow of gases to
equalize the pressure
What are the characteristics of the respiratory cycle at rest? - ANSWER-Alveolar pressure equals
atmospheric pressure
Because lung pressures are expressed relative to atmospheric pressure, alveolar pressure is said to
be zero
