Respiratory System

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Respiratory System
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Functions

• Gas exchange respiration series of events that
  includes ventilation, external respiration,
  transport of gases internal respiration
• Regulation of blood pH reliant on CO2 levels
• Voice production in larynx
• Olfaction sense of smell CN I
• Protection mucus membranes, cilia

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terminology

• Respiration exchange of carbon dioxide and
  oxygen between atmosphere and body cells
• External respiration exchange of gases at level
  of lungs
• Internal respiration exchange of gases at
  tissue level
• Ventilation breathing
• inspiration inhalation
• expiration -exhalation

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Upper respiratory tract nose, sinuses, pharynx
larynx Lower respiratory tract trachea,
bronchial tree lungs
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Nose nasal bones and cartilage Nasal cavity is
separated by septum formed by vomer
perpendicular plate of ethmoid Rhinitis
inflammation of nasal mucusa excessive mucus
production. Can be caused by virus, bacteria or
irritants.
Sinuses air filled cavities Reduce the weight of
the skull Produce mucus Influence voice quality
act as resonating chambers
Pharynx throat. Nasophayrnx posterior to the
nasal cavity and extend to uvula. Oropharynx
posterior to the oral cavity extends from uvula
to the hyoid bone. Laryngopharynx from hyoid
bone to the larynx
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Larynx also known as the voice box Passageway
for air. 9 cartilages hyaline except for
epiglottis, which is elastic. During swallowing,
epiglottis covers respiratory tract Thyroid
cartilage Adam's apple
Vocal cords- vestibular folds /false vocal cords,
help to keep particles out of respiratory tract.
True vocal cords controlled by muscles that
change tension for speaking. Opening between
true cords is called glottis.
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Trachea windpipe. Supported by 15-20 C
shaped rings Lined with a pseudostratified
columnar epithelium similar to nasal passages.
Has ciliary escalator Divides into the right and
left bronchi
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The bronchial tree begins after the last tracheal
ring the carina. The right bronchi is shorter
and more vertical. The bronchi branch into
smaller and more numerous branches. The smallest
bronchi are called bronchioles. They lead to the
alveolar ducts which terminate in the air sacs
known as alveoli. Bronchioles are primarily
composed of smooth muscle. Alveoli are primarily
simple squamous epithelium. This allows rapid
diffusion of oxygen and carbon dioxide. Area of
gas exchange external respiration.
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The lungs contain the bronchial tree and alveoli.
They are soft and spongy. The lungs are encased
by a double layered serous membrane called the
pleura. The left has the cardiac notch.
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terminology

• Respiration exchange of carbon dioxide and
  oxygen between atmosphere and body cells
• External respiration exchange of gases at level
  of lungs
• Internal respiration exchange of gases at
  tissue level
• Ventilation breathing
• inspiration inhalation
• expiration -exhalation

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Breathing is dependant on muscle movement and air
pressure
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Oxygenated air rushes down tract to the alveolar
sacs where external respiration occurs. The
exchange of gases is driven by CO2 diffusion.
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External Respiration
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Gases are transported by the blood. RBCs are
primarily responsible for O2 transport, and the
plasma transports the majority of the CO2.
Hemoglobin Oxygen ? Oxyhemoglobin Hb
O2 ? HbO2
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Oxyhemoglobin ---? Hemoglobin Oxygen
HbO2 ? Hb O2
Carbon Dioxide Hemoglobin ?
Carbaminohemoglobin CO2
Hb ? HbCO2
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Carbon Dioxide is transported 70 in the plasma
as bicarbonate ions driven by carbonic
anhydrase enzyme carried by RBCs 23 combines
with Hb to form HbCO2 7 dissolves in the plasma
and is carried as CO2
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