The Human Respiratory System

1
The Human Respiratory System

• Mrs. Berlingers Sixth Period
• November 12, 2001

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Inhaling

• Take in oxygen from air
• Oxygen enters into the nasal passages and mouth
• Diaphragm moves downward

3
Nasal Cavity

• Oxygen is moistened and warmed
• Oxygen is filtered by nose hairs (cilia) and
  mucus
• Filtered for pollen, dust, and bacteria

4
Pharynx

• Both food from the mouth and oxygen from the
  nasal cavity go through pharynx
• Tube-like passageway
• Oxygen from mouth and nose meet in pharynx

5
Epiglottis

• Closes over trachea when food goes by
• Flap of skin at bottom of pharynx
• Acts like a door

6
Larynx

• Oxygen, from the pharynx, enters larynx and
  vibrates vocal chords to make sounds
• At top of trachea
• Location of vocal chords

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Trachea

• As oxygen passes larynx into rest of trachea, it
  traps dust and pollen
• Average tube of 12 cm
• Oxygen goes through trachea to bronchi

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Trachea (cont.)

• Has c-shaped rings of cartilage to keep trachea
  open and stiff

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Bronchi

• Passageway from trachea to lungs for oxygen to
  travel
• Splits into two paths each called a bronchus

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Bronchioles

• Passageways keep splitting
• Oxygen moves from bronchi through bronchioles

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Alveoli (Air Sacs)

• Oxygen and carbon dioxide trade places
• One alveolus at the end of each bronchiole
• Large bundles of alveoli make up your LUNGS

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Alveoli (cont.)

• Oxygen sent to cells by blood
• Carbon dioxide and other waste brought back to
  alveoli by blood

13
Exhaling

• Diaphragm moves upward
• Carbon dioxide moves from alveoli into the
  bronchioles
• Carbon dioxide moves from bronchioles through
  bronchi

14
Exhaling (cont.)

• From bronchi carbon dioxide enters the trachea
• Carbon dioxide passes the larynx, exits the
  trachea, into the pharynx
• Carbon dioxide EXITS THE BODY through nose and
  mouth