Respiratory System Flashcards
What are the 4 functions of the respiratory system?
- transfer of gases between air and blood
- regulation of body pH
- defence from inhaled pathogens
- vocalization
Describe the structure of the respiratory system.
upper respiratory tract:
nasal cavity, tongue > pharynx > vocal cords > larynx > esophagus
lower:
trachea > l/r bronchus > l/r lung > diaphragm
What are the muscles of inspiration and expiration?
insp: sternocleidomastoids, scalenes, external intercostals, diaphragm
exp: internal intercostals, abdominal muscles
What encloses the lungs?
pleural sacs
How is the air prepared for the alveoli?
With several branch offs, the air is:
- warmed to 37C
- humidified to 100%
- filtered (nose+cilia)
How is gas exchanged in the alveoli?
passive diffusion
How does the respiratory system protect from pathogens?
- filtering in the nose
- mucous and action of cilia in airways
- antibodies secreted into respiratory surfaces
- macrophages in respiratory tract and alveoli
Inspiratory/expiratory reserve volume
breathe in/out as much as you can
total lung capacity
total amount of air you can have in your lungs
obstructive lung diseases
more airway resistance, smaller ERV bigger RV greater TLC
ie. asthma
inspiratory restrictive lung disease
less compliant lung, small TLC
ie. pulmonary fibrosis
expiratory restrictive lung disease
organs push diaphragm upward, unable to exhale as easily
ie. obesity
What is the normal forced expiratory volume and forced vital capacity with definitions?
FEV - 4.0 volume of air forcefully exhaled in first second
FVC - 5.0 volume of air forcefully exhaled
80%
FEV and FVC in obstructive lung disease
FEV = 1.3
FVC = 3.1
42%
low FEV means problems w air escaping lungs
low FVC problems with air escaping all points
FEV and FVC in restrictive lung disease
FEV = 2.8
FVC = 3.1
90%
