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The Respiratory System
M
ountainclimbingcan be a dangerous sport.
As you climb, ascending higher and higher
through the Earth’s atmosphere, the atmospheric
pressure decreases. As the atmospheric pressure
decreases, so does the concentration of oxygen
in the air. Climbers can experience dizziness and
may even faint if the oxygen concentration gets
too low. To cope with the effects of high altitudes,
climbers make extended stops in base camps
located at various altitudes along the way to their
destination. During these rest stops, their bodies
adjust (acclimate) to the decreased oxygen levels.
As they are acclimating, their breathing becomes
rapid and their hearts beat faster. Climbers also
use bottled oxygen to counteract the deficit.
The same effects can be felt when acclimating
to a high-altitude city such as Denver, Colorado,
the “Mile-High City.” When visiting sports teams
from cities at lower altitudes play the home teams
in Denver, they often travel to the city early to give
their players a chance to acclimate; in addition,
they supply oxygen on the sidelines. Others who
experience high altitudes include fighter pilots,
astronauts, and passengers and crew members on
commercial flights; commercial aircraft and space
vehicles must maintain pressurized cabins so
that their passengers have sufficient oxygen, and
fighter pilots wear oxygen masks.
In this chapter, you will learn how your body
takes in oxygen and removes carbon dioxide via
the respiratory system. Let’s take a look at this
amazing system that permits your body to make
use of the oxygen from the air through mechanical
ventilation and gas exchange.
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GEOGRAPHIC
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