Download Respiratory System

Respiratory System
Mrs. Hartley
Physiology
Functions
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Brings oxygen into the
bloodstream where it can
be transported to all
body cells
Removes the waste
product carbon dioxide
from the blood and
channels it outside the
body
Organs of System
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Upper respiratory tract: head and neck; nose,
pharynx and larynx
Lower respiratory tract: thoracic cavity; trachea,
bronchi, bronchioles and alveoli
Conduction zone: nose, pharynx, trachea,
bronchi and bronchioles
Respiratory zone: alveoli and capillaries; gas
exchange
Nose
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Initial receiving chamber for
inhaled air
External nares: nostrils
Separated by nasal septum
into vestibule into nasal
cavity through nasal conchae
Abundant blood vessels
Warm the air then move to
pharynx by action of cilia
Mucus traps bacteria and
dust
Pharynx
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Back of nasal cavity to
the larynx
Received air from nasal
cavity
Nasopharynx,
oropharynx,
laryngopharynx
Larynx
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Connects pharynx with the
trachea
Prevents solid material from
entering the trachea
Carilage arranged in boxlike
structure; Adam’s Apple
Attached to vocal cords and
muscles of the throat
Epiglottis protects food from
trachea by closing over it
during swallowing
Trachea
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Tubular air passage about
12cm long and 2.5cm wide
Extends from the larynx
downward into the thoracic
cavity where it divides into
right and left bronchi
Rings of cartilage, smooth
muscle, and elastic fibers
Ciliated mucous membrane;
conveyor belt
Keeps microorganisms, dust
particles and noxious gases
from reaching alveoli in lungs
Bronchial Tree
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Primary bronchi; right
and left
Bronchial tree – divisions
within the lungs
Alveolar ducts
Alveoli
Passageway for air
between the trachea and
alveoli
Lungs
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Bronchial tree, alveoli, capillary networks and
supportive tissues
Site of gas exchange between the atmosphere
and the bloodstream
Soft, spongy organs; 3 right lobes; 2 left lobes
Parietal pleura on outside of lung; visceral on
inside layer; pleural cavity between the two
Breathing Mechanics
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Inspiration
Expiration
Pulmonary Ventilation:
“breathing”; exchange of
air between external
environment and alveoli
of lungs
Inspiration
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Diaphragm and external
intercostal muscles
contract
Thoracic cavity expands
Lung volume expands
Alveolar pressure falls
Air rushes from high to
low; outside to inside
Expiration
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Diaphragm and external
intercostal muscles relax
Lung volume decreases
Alveolar pressure
increases more than
atmospheric pressure
Air flows from high to
low; air moves out
Types of Respiration
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Pulmonary Ventilation: “breathing”
External respiration: exchange of gas between alveoli
and bloodstream
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Oxygen binds to hemoglobin of RBCs
Carbon dioxide moves out of blood and into alveoli
Internal Respiration: exchange of gases between capillaries
and body cells
 Oxygen leaves blood to nourish cells
 Carbon dioxide is picked up from cells to be breathed out
in lung