The Circulatory System
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Human circulatory system
A circulatory system consists of a
group of organs that assist the
movement of substances, such as
oxygen and glucose, around the body.
Humans and other complex
organisms have a closed circulatory
system where blood is contained
within a series of vessels. This
allows the speed, pressure and
distribution of blood to be controlled.
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Double circulatory system advantages
The double circulatory system produces higher pressures
in blood vessels than a single circulatory system can.
This creates a greater
rate of blood flow to
the tissues.
The greater rate of flow allows blood to be pumped quickly
even through the bodies of large mammals, like elephants
and whales.
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