Respiratory system
a
Nasal cavity
b
Pharynx
Nasopharynx
b2 Oropharynx
b3 Laryngopharynx
b1
c
Larynx
d
Trachea
e
Lung
Superior lobe
e2 Middle lobe
e3 Inferior lobe
e1
Primary bronchi
g
Diaphragm
Sphenoid sinus
Vestibule
a
Upper respiratory tract
f
Frontal sinus
External naris (nostril)
b1
Oral cavity
b2
b3
c
Epiglottis
d
Lower respiratory tract
Ribcage
e1
f
f
e1
Cardiac notch
e2
e3
g
e3
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