The Respiratory System
Dr. Wendy Bruffy
Fun Facts
• Why Do I Yawn?
When you are sleepy or drowsy the lungs
do not take enough oxygen from the air. This
causes a shortage of oxygen in our bodies. The
brain senses this shortage of oxygen and
sends a message that causes you to take a
deep long breath---a YAWN.
Facts Cont.
• Why Do I Sneeze?
Sneezing is like a cough in the upper
breathing passages. It is the body's way of
removing an irritant from the sensitive
mucous membranes of the nose. Many things
can irritate the mucous membranes. Dust,
pollen, pepper or even a cold blast of air are
just some of the many things that may cause
you to sneeze.
Facts Cont.
• What Causes Hiccups?
Hiccups are the sudden movements of the
diaphragm. It is involuntary --- you have no
control over hiccups, as you well know. There
are many causes of hiccups. The diaphragm
may get irritated, you may have eaten to fast,
or maybe some substance in the blood could
even have brought on the hiccups.
The Respiratory System
• What is the respiratory system?
Your respiratory system is made up of the
organs in your body that help you to breathe.
• Respiration = Breathing.
• The goal of breathing is to deliver oxygen to
the body and to take away carbon dioxide.
Parts of the Respiratory System
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Nose & Mouth
Trachea
Bronchi
Bronchioles
Diaphragm
Lungs
The Nose & Mouth
• The 1st places O2 enters.
• Both enter into the pharynx
• Both have protective measures to aid against foreign
matter
Trachea
• The trachea (TRAY-kee-uh} is sometimes called
the windpipe. The trachea filters the air we
breathe and branches into the bronchi.
Bronchi
• Bronchi
The bronchi (BRAHN-ky) are two air tubes
that branch off of the trachea and carry air
directly into the lungs.
Bronchiole
• The bronchioles are smaller than the bronchi
and branch out to the alveoli. The alveoli are
the grape like clusters that are surrounded by
capillaries and the location of gas exchange in
the lung. There are 600 million alveoli.
Diaphragm
• Diaphragm
Breathing starts with a dome-shaped muscle at
the bottom of the lungs called the diaphragm
(DY-uh-fram). When you breathe in, the
diaphragm contracts. When it contracts it flattens
out and pulls downward. This movement enlarges
the space that the lungs are in. This larger space
pulls air into the lungs. When you breathe out,
the diaphragm expands reducing the amount of
space for the lungs and forcing air out. The
diaphragm is the main muscle used in breathing.
Lungs
• Lungs
The lungs are the main organs of the respiratory
system. In the lungs oxygen is taken into the body and
carbon dioxide is breathed out. The red blood cells are
responsible for picking up the oxygen in the lungs and
carrying the oxygen to all the body cells that need it.
The red blood cells drop off the oxygen to the body
cells, then pick up the carbon dioxide which is a waste
gas product produced by our cells. The red blood cells
transport the carbon dioxide back to the lungs and we
breathe it out when we exhale.
Breathing
• Breathing is usually automatic, controlled subconsciously by the
respiratory center at the base of the brain.
• Breathing continues during sleep and usually even when a person is
unconscious.
• People can also control their breathing when they wish, for example
during speech, singing, or voluntary breath holding.
• Sensory organs in the brain and in the aorta and carotid arteries monitor
the blood and sense oxygen and carbon dioxide levels.
• Normally, an increased concentration of carbon dioxide is the strongest
stimulus to breathe more deeply and more frequently.
• Conversely, when the carbon dioxide concentration in the blood is low, the
brain decreases the frequency and depth of breaths.
• During breathing at rest, the average adult inhales and exhales about 15
times a minute.