How does blood travel through your body?
As the heart beats, it pumps blood through a system of
blood vessels, called the circulatory system. The vessels are elastic
tubes that carry blood to every part of the body.
Blood is essential.
- It carries oxygen and nutrients
to your body's tissues
- It takes carbon dioxide and waste
products away from the tissues.
- It is needed to sustain life and
promote the health of all the body’s tissues.
There are three main types of blood vessels:
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- The arteries
(red) carry oxygen and nutrients away from your heart, to your
body's tissues.
- The veins
(blue) take oxygen-poor blood back to the heart
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Arteries
- Arteries begin with the aorta, the
large artery leaving the heart.
- They carry oxygen-rich blood away
from the heart to all of the body’s tissues.
- They branch several times, becoming
smaller and smaller as they carry blood further from the heart.
Capillaries
- Capillaries are small, thin blood
vessels that connect the arteries and the veins.
- Their thin walls allow oxygen, nutrients,
carbon dioxide and waste products to pass to and from the tissue cells.
Veins
- These are blood vessels that take
oxygen-poor blood back to the heart.
- Veins become larger and larger as
they get closer to the heart.
- The superior vena cava is the large
vein that brings blood from the head and arms to the
heart, and the inferior vena cava brings blood from the abdomen and
legs into the heart.
This vast system of blood vessels — arteries, veins,
and capillaries — is
over 60,000 miles long. That's long enough to go around the world more
than twice!
Blood flows continuously through your body's blood vessels.
Your heart is the pump that makes it all possible.
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