Transcript Respiration

The Respiratory System
Breathe in
Breath out
What Does the Respiratory
System Do?
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Brings oxygen in
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Lets carbon dioxide out
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Waste product made by the
cells
Together, this system is called
Respiration
The Pathway of Air...
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Enters the body through mouth and
nasal cavities
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Flows into the pharnyx (throat)
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Then to the larynx (voice box)
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The trachea (windpipe) then carries air
to the lungs
How Does it Flow?
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The rib muscles and diaphragm pull air
in and out
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contract = in
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relax = out
What Controls Breathing Rate?
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Centers in the brain stem detect carbon dioxide in the blood
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Carbon dioxide is toxic = it must not build up in blood
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Brain stem signals diaphragm to contract more = breathe faster =
rids system of excess carbon dioxide
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When too little carbon dioxide, the opposite happens