Respiratory System Overview
Nasal Cavity
• Warms and moistens
air so that it doesn’t
damage the
respiratory tract.
• Dust and debris is
also removed by
short hairs and
mucous.
Pharynx
• “Back of the throat”
• Shared by both the
respiratory tract and
digestive tract
• Leads to the
esophagus and
larynx
Larynx
• “Voice box”
• Contains the glottis (the opening to the larynx
and trachea)
• Protected by a piece of cartilage called the
epiglottis, which closes during swallowing.
• The opening is lined by elastic tendons called
vocal cords; small muscles change the tension
in these tendons.
Larynx
Larynx
Trachea
• “Windpipe”
• Tough, flexible tube that branches into the
right and left bronchi of each lung.
• Carries air from the throat to the lungs
• The walls of the trachea are supported by
tracheal cartilage (“C” shaped cartilage that
prevents the trachea from collapsing)
Trachea
Bronchi
• Conducts air into lungs.
• The right and left primary bronchi divide into
smaller passageways called secondary and
tertiary bronchi. These divide into even
smaller passageways called bronchioles.
• Tubes supported by cartilage.
Bronchi
Alveoli
• The end of the respiratory tract where gas
exchange between blood and air takes place.
Diaphragm
• Skeletal muscle that divides the thoracic and
abdominal cavities.
• Contraction of the diaphragm causes air to
into the lungs (inhalation). Relaxation of
diaphragm causes air to exit lungs
(exhalation).
Diaphragm