How Your Body Uses Oxygen

How Your Body Uses Oxygen
Oxygen is a gas that your body uses for energy. It is needed by your body
cells to keep them alive. Being able to move and think require your body to
have oxygen. This handout will talk about how your body uses oxygen.
How do you get oxygen in your body?
Oxygen is found in the air around
you, along with nitrogen and other
gases. When you take a breath, air
goes in through your nose and
mouth. It passes through your
trachea or windpipe and into
airways called bronchi (BRAWNki) in your lungs. The airways
branch off into smaller and smaller
openings. At the end of the openings
are alveoli (al-VEE-o-lie), or tiny air
sacs. The air bounces around in
these tiny air sacs and blood cells in
the very small blood vessels around
these air sacs pick up oxygen.
These very small blood vessels are
called capillaries (KAP-e- ler-ees). Capillaries connect your arteries and
veins. They are found all over your body. It is in these small blood vessels
in your lungs that oxygen gets into your blood. This oxygen rich blood then
goes back into the left side of your heart where it gets pumped out to all
parts of your body through your arteries.
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Page 2
What happens when the oxygen is carried to the cells?
Through the rest of your body, these small blood vessels or capillaries are
where oxygen is dropped off to your cells and waste products, like carbon
dioxide are picked up. The waste products are then carried in your blood
through your veins back to the right side of your heart.
When the blood gets
back to your heart,
there is very little
oxygen left in it, and
there are larger
amounts of waste
products. The blood
goes into the right
side of your heart and
then gets pumped
back into your lungs.
The gray area in the
picture shows this.
The waste gases, like
carbon dioxide, are
passed from the blood
through the capillaries
into the air sacs. They
are then breathed out
through your lungs while more oxygen is being picked up by your blood
cells. This air exchange happens quickly and often.
There is a chemical in your blood called hemoglobin (HE-mo-glow-bin).
This is what picks up and carries the oxygen in your blood. When there is
oxygen, the hemoglobin turns bright red in color. As the oxygen is dropped
off to the cells, the hemoglobin turns a darker red or purple color. This
color change is what is used during a pulse oximeter reading to give your
oxygen level.
Talk to your doctor or others on your health care team if you have
any questions. You may request more written information from the
Library for Health Information at (614) 293-3707 or email:
[email protected]