Respiratory-1 Flashcards
where does gas exchange occur
alveoli
where does gas exchange occur
alveoli
as a result of alveolar cells being flat & tiny & having them share a basement membrane ->
barrier for diffusion is kept minimal
majority of alveolar cells are type
1
cells that secrete surfactant, & reabsorb sodium & water are type
2
purpose of alveoli containing pores
to allow air passage among alveoli in sac
location of alveoli clusters/sacs
at ends of respiratory bronchioles
thin air tubes at ends of respiratory bronchioles
alveoli sacs/clusters
alveoli contain individual alveoli as out-pouchings along length
t
respiratory tree:
terminal bronchioles -> respiratory bronchioles -> alveoli -> alveoli clusters
gas exchange only occurs in areas with
alveoli
respiratory zone
region where gas exchange occurs (respiratory bronchioles, alveolar sacs, alveoli)
conducting zone
structures that carry air to respiratory zone; warming & humidifying of air, filters particles
mucociliary escalator
traps inhaled particles that would find way into alveoli & cause problems w/ gas exchange
macrophages deal with particles
LESS THAN 6 uM
trachea is __ to esophagus
anterior
cartilaginous rings of trachea important for
keeping airway open so it doesn’t collapse
diaphragm shape at rest
dome
diaphragm shape at contraction
flat
parietal pleura
lines cavity
visceral pleura
covers lungs
pleural cavity
potential space between membranes
thin layer of fluid secreted by
parietal pleura
for air to enter lungs, atmospheric pressure must be __ than intrapulmonary pressure
greater
for air to leave lungs, atmospheric pressure must be __ than intrapulmonary pressure
less
what allows changes in atmospheric & intrapulmonary pressures
changes in vol of thoracic cavity
breathe in ->
diaphragm contracts (flattens) -> vol increases -> ribs swing up & out -> further increased vol in thoracic cav -> pressure gets below atmospheric -> air ENTERS
breathing is a __ process
passive
breathe out ->
diaphragm relaxes (dome shape) -> structures of thoracic cage recoil -> decreased vol of thoracic cav -> pressure rises above atmospheric -> air OUT
does resting exhalation require energy?
no (passive)
does resting inhalation require energy?
yes (to contract intercostals & diaphragm)
forced inhalation is the same as resting inhalation, it just required more muscles to further expand vol of thoracic cav to really reduce pressure & have air come in more forcefully
t
the more resistance to air flow, the more
difficult to get air in to or out of lungs
__ must be rigid to protect organs, yet distensible for breathing
thorax
atmospheric > intrapulmonary
inhalation (resting)
what is needed during forced inhalation other than more muscles?
negative intra-pleural pressure: visceral pleura clings to lungs, parietal pleura clings to ribs -> aids in lung expansion
what would happen if intra-pleural pressure is not < intrapulmonary pressure?
lung collapse
intrapulmonary > atmospheric
exhalation (resting)
pressure difference across wall of lung aka
transpulmonary pressure
intrapleural always has to be __ than intrapulmonary
ease of expansion
aka compliance
a compliant lung
expands easily
a noncompliant lung
does not expand easily & need to add a lot of pressure
factors that reduce compliance
pulmonary fibrosis & a positive intrapleural pressure
ability to return to original size after distension aka
elasticity
compliance important for
inhaling
elasticity important for
fully exhaling
when air enters into intrapleural space known as a
pneumothorax (lung cannot expand & will collapse)
surface tension refers to
water molecules liking to stick to each other (thin layer)
surface tension important for
gas exchange
each alveoli has low amount of fluid
t
why is surface tension problematic?
water molecules like to stick to each other so when you exhale & alveoli get smaller, water molecules create more force & it becomes difficult for alveoli to reinflate
what guards against the problem of surface tension?
surfactant produced by TYPE 2 alveolar cells
surfactant production occurs late in fetal life
t
surfactant is a
soapy film that reduces h bonds between water molecules to reduce surface tension, making it easy for lungs to reinflate
pulmonary function test that measures lung vol & detects lung disorders
spirometry
resting inhalation & exhalation
tidal vol
amount you can inhale over norm tidal inhalation
inspiratory reserve vol
amount you can exhale over norm tidal exhalation
expiratory reserve vol
amount you cannot get out of lungs no matter what
risidual vol
what remains in your lungs after a norm tidal exhalation
functional risidual capacity
tidal vol + erv + irv
vital capacity
vital capacity + residual vol
total lung capacity
capacities =
sum of 2 or more lung vol’s
tv x respirations/min =
total min vol or min resp vol
total min vol is about
6L/min (at rest)
not all inspired air reaches alveoli b/c some required to fill conducting division. this refers to
anatomical dead space
can anatomical dead space be used for gas exchange?
no
anatomical dead space + non-exchanging area of respiratory division refers to
physiological dead space
anatomical & physiological dead spaces are __ in a healthy individual
identical
restrictive disorders are when
lungs are stiffened; compliance greatly reduced
pulmonary fibrosis is a __ disorder
restrictive
obstructive disorders are when
recoil & exhalation are affected
COPD, emphysema & asthma are __ disorders
obstructive
in restrictive disorders, vital capacity & compliance are __, exhalation vol is __; FEV1 is __
reduced; ok; norm/elevated
in obstructive disorders, vital capacity is; FEV1 is __
normal; reduced
FEV means
forced expiratory vol
FEV1 means
amount out in 1 sec
FVC means
as much air in as possible
in a healthy individual, FEV1 is
80% of what was taken in
FEV1/FVC ratio < 80% indicative of
obstructive disease
FEV1/FVC ratio > 80% indicative of
restrictive disorder (bc recoil is great, vol will be low, normally 90% of what got in)
as a result of alveolar cells being flat & tiny & having them share a basement membrane ->
barrier for diffusion is kept minimal
majority of alveolar cells are type
1
cells that secrete surfactant, & reabsorb sodium & water are type
2
purpose of alveoli containing pores
to allow air passage among alveoli in sac
location of alveoli clusters/sacs
at ends of respiratory bronchioles
thin air tubes at ends of respiratory bronchioles
alveoli sacs/clusters
alveoli contain individual alveoli as out-pouchings along length
t
respiratory tree:
terminal bronchioles -> respiratory bronchioles -> alveoli -> alveoli clusters
gas exchange only occurs in areas with
alveoli
respiratory zone
region where gas exchange occurs (respiratory bronchioles, alveolar sacs, alveoli)
conducting zone
structures that carry air to respiratory zone; warming & humidifying of air, filters particles
mucociliary escalator
traps inhaled particles that would find way into alveoli & cause problems w/ gas exchange
macrophages deal with particles
LESS THAN 6 uM
trachea is __ to esophagus
anterior
cartilaginous rings of trachea important for
keeping airway open so it doesn’t collapse
diaphragm shape at rest
dome
diaphragm shape at contraction
flat
parietal pleura
lines cavity
visceral pleura
covers lungs
pleural cavity
potential space between membranes
thin layer of fluid secreted by
parietal pleura
for air to enter lungs, atmospheric pressure must be __ than intrapulmonary pressure
greater
for air to leave lungs, atmospheric pressure must be __ than intrapulmonary pressure
less
what allows changes in atmospheric & intrapulmonary pressures
changes in vol of thoracic cavity
breathe in ->
diaphragm contracts (flattens) -> vol increases -> ribs swing up & out -> further increased vol in thoracic cav -> pressure gets below atmospheric -> air ENTERS
breathing is a __ process
passive
breathe out ->
diaphragm relaxes (dome shape) -> structures of thoracic cage recoil -> decreased vol of thoracic cav -> pressure rises above atmospheric -> air OUT
does resting exhalation require energy?
no (passive)
does resting inhalation require energy?
yes (to contract intercostals & diaphragm)
forced inhalation is the same as resting inhalation, it just required more muscles to further expand vol of thoracic cav to really reduce pressure & have air come in more forcefully
t
the more resistance to air flow, the more
difficult to get air in to or out of lungs
__ must be rigid to protect organs, yet distensible for breathing
thorax
atmospheric > intrapulmonary
inhalation (resting)
what is needed during forced inhalation other than more muscles?
negative intra-pleural pressure: visceral pleura clings to lungs, parietal pleura clings to ribs -> aids in lung expansion
what would happen if intra-pleural pressure is not < intrapulmonary pressure?
lung collapse
intrapulmonary > atmospheric
exhalation (resting)
pressure difference across wall of lung aka
transpulmonary pressure
intrapleural always has to be __ than intrapulmonary
less than
ease of expansion
aka compliance
a compliant lung
expands easily
a noncompliant lung
does not expand easily & need to add a lot of pressure
factors that reduce compliance
pulmonary fibrosis & a positive intrapleural pressure
ability to return to original size after distension aka
elasticity
compliance important for
inhaling
elasticity important for
fully exhaling
when air enters into intrapleural space known as a
pneumothorax (lung cannot expand & will collapse)
surface tension refers to
water molecules liking to stick to each other (thin layer)
surface tension important for
gas exchange
each alveoli has low amount of fluid
t
why is surface tension problematic?
water molecules like to stick to each other so when you exhale & alveoli get smaller, water molecules create more force & it becomes difficult for alveoli to reinflate
what guards against the problem of surface tension?
surfactant produced by TYPE 2 alveolar cells
surfactant production occurs late in fetal life
t
surfactant is a
soapy film that reduces h bonds between water molecules to reduce surface tension, making it easy for lungs to reinflate
pulmonary function test that measures lung vol & detects lung disorders
spirometry
resting inhalation & exhalation
tidal vol
amount you can inhale over norm tidal inhalation
inspiratory reserve vol
amount you can exhale over norm tidal exhalation
expiratory reserve vol
amount you cannot get out of lungs no matter what
risidual vol
what remains in your lungs after a norm tidal exhalation
functional risidual capacity
tidal vol + erv + irv
vital capacity
vital capacity + residual vol
total lung capacity
capacities =
sum of 2 or more lung vol’s
tv x respirations/min =
total min vol or min resp vol
total min vol is about
6L/min (at rest)
not all inspired air reaches alveoli b/c some required to fill conducting division. this refers to
anatomical dead space
can anatomical dead space be used for gas exchange?
no
anatomical dead space + non-exchanging area of respiratory division refers to
physiological dead space
anatomical & physiological dead spaces are __ in a healthy individual
identical
restrictive disorders are when
lungs are stiffened; compliance greatly reduced
pulmonary fibrosis is a __ disorder
restrictive
obstructive disorders are when
recoil & exhalation are affected
COPD, emphysema & asthma are __ disorders
obstructive
in restrictive disorders, vital capacity & compliance are __, exhalation vol is __; FEV1 is __
reduced; ok; norm/elevated
in obstructive disorders, vital capacity is; FEV1 is __
normal; reduced
FEV means
forced expiratory vol
FEV1 means
amount out in 1 sec
FVC means
as much air in as possible
in a healthy individual, FEV1 is
80% of what was taken in
FEV1/FVC ratio < 80% indicative of
obstructive disease
FEV1/FVC ratio > 80% indicative of
restrictive disorder (bc recoil is great, vol will be low, normally 90% of what got in)
