Respiratory System
Don’t worry, just breathe!
(More corny jokes to come)
Parts of respiratory
system
•
•
•
•
•
•
•
Nasal cavity
Oral cavity
Trachea
Bronchi
Lung
Alveoli
Diaphragm
Functions of upper respiratory tract:
nasal/oral cavities and trachea
• Nose/Mouth:
• Filters air, Warms air, Moistens
air
• Larynx: “voice box” Holds our
vocal chords.
• Trachea:
• Commonly called your “wind
pipe.” Air travels down it to
your lungs
Functions of the lower respiratory tract:
bronchi, lung, alveoli, diaphragm
• Bronchi:
Branches that
“stem” off of the
trachea and lead
to lungs.
• Divides into
smaller tubes
called
bronchioles.
Functions of Lungs
• Lung: Holds bronchi, bronchioles, and alveoli.
• Fact: Lungs are the only organ in the body that
can float on water.
Function of Alveoli
• Alveoli: Lungs contain approx. 600 million
alveoli. Where exchange of oxygen (from
air) and carbon dioxide (from body)
occurs.
Function of diaphragm
• Diaphragm: Responsible for breathing.
When the diaphragm contracts, the
ribcage expands and the contents of the
abdomen are moved downward. When the
diaphragm relaxes, the air is forced out of
the body.
What’s a hiccup?
• Ever wonder what a hiccup is? It’s an
involuntary spasm of the diaphragm that
forces air out of the lungs. The blast of air
speeds through the vocal chords making
the familiar hiccup sound.
• How do you cure hiccups? There are over
50 methods believed to get rid of hiccups.
What have you heard?
Why do we yawn?
• There are lots of theories as to why people
yawn. Some say it’s a way to get lots of oxygen
into our bodies at once. Others say it’s our
bodies way of clearing out stale air in our lungs.
Even some say it’s like stretching the blood
vessels in our jaws when we haven’t spoken in a
while. People often also make a connection with
yawning and boredom (but not in health class).
Whatever causes yawning, one thing’s for
sure…it’s contagious!
Nasal Cavity
Oral Cavity
throat
Larynx
(Voice Box)
Trachea
Lung
Bronchi
Bronchioles
Diaphragm
Alveoli
Review
• Define vocabulary words on pg. 428 (6
words) and 432 (7 words)
Time to meet Slim Good Body