Circulation - The Body’s Transport System
Circulation:
The Body’s
Transport
System
Circulation - The Body’s Transport System
How do the nutrients you
absorb in digestion get from
the small intestine to different
parts of your body?
How does the oxygen you
breathe get to your working
muscles during exercise?
Circulation - The Body’s Transport System
The
Circulatory
System!
Circulation - The Body’s Transport System
What is the CIRCULATORY
SYSTEM?
• A “HIGHWAY” NETWORK
that LINKS all parts of
your body.
• Consists of the HEART, BLOOD
VESSELS, and BLOOD.
Circulation - The Body’s Transport System
What is the FUNCTION of the
circulatory system?
1) To DELIVER NEEDED SUBSTANCES
TO CELLS. (ex. oxygen and glucose)
2) To REMOVE WASTE PRODUCTS,
carrying them AWAY from cells.
3) To FIGHT DISEASE by carrying white
blood cells to source of disease.
Circulation - The Body’s Transport System
How does the
circulatory system work?
• The HEART is the
PUMP that makes it
work.
• Each time the HEART
BEATS, it PUSHES
BLOOD through the
BLOOD VESSELS of
the circulatory system.
Circulation - The Body’s Transport System
What does the HEART look like?
• The heart is a HOLLOW,
MUSCULAR organ that
pumps your blood.
• The RIGHT and LEFT
SIDES of the heart are
completely SEPARATED
by a wall of tissue called
the SEPTUM.
Circulation - The Body’s Transport System
What does the HEART look like?
• Each side of the heart
has 2 CHAMBERS (4 all
together).
• The upper chamber is
called an ATRIUM.
• The lower chamber is
called a VENTRICLE.
Circulation - The Body’s Transport System
What does the HEART look like?
• VALVES SEPARATE the
chambers and prevent
blood from FLOWING in
the WRONG
DIRECTION.
Circulation - The Body’s Transport System
How does the HEART pump?
• When the strong MUSCLES
around the VENTRICLES
contract, they exert a FORCE
on the blood.
• This force PUSHES the blood
OUT of the heart INTO THE
ARTERIES.
Circulation
Circulation - The Body’s Transport System
Where does the blood go
after it leaves the HEART?
• After leaving the heart, the
blood travels in TWO
LOOPS.
• The LOOPS are the CIRCLE
part of the CIRCULATORY
system.
Circulation - The Body’s Transport System
Where does the blood go
after it leaves the HEART?
• In the FIRST LOOP, blood
travels from the HEART TO
THE LUNGS AND BACK.
• At the LUNGS, the blood gets
RID OF CARBON DIOXIDE
and PICKS UP OXYGEN.
Circulation - The Body’s Transport System
Where does the blood go
after it leaves the HEART?
• In the SECOND LOOP, blood
travels from the HEART OUT
TO THE BODY AND BACK.
• After the first loop, the blood
is OXYGEN-RICH and
DELIVERS OXYGEN out to
the body where it is USED BY
MUSCLES.
Circulation
Why is it
important that
the septum
separates the
left and right
sides of the
heart?
Circulation - A Closer Look at Blood Vessels
What are BLOOD VESSELS?
• BLOOD VESSELS are
the HOLLOW TUBES
that carry your blood
around your body.
• There are 3 TYPES:
1) ARTERIES
2) CAPILLARIES
3) VEINS
Circulation - A Closer Look at Blood Vessels
What are ARTERIES?
• ARTERIES carry blood
AWAY FROM THE
HEART.
• They have THICK,
MUSCULAR walls that
are STRONG and
FLEXIBLE and can
stand the enormous
PRESSURE created by
the heart.
Circulation - A Closer Look at Blood Vessels
What are CAPILLARIES?
• CAPILLARIES are TINY
vessels that run all
through your BODY’S
TISSUE.
• The WALLS are very
THIN to allow OXYGEN
and WASTES to be
exchanged between
BLOOD and CELLS.
Circulation - A Closer Look at Blood Vessels
What are VEINS?
• VEINS carry blood
BACK TO THE HEART.
• They have THINNER
WALLS than arteries
do, because there is
much LESS
PRESSURE from the
heart.
Circulation - A Closer Look at Blood Vessels
Circulation - A Closer Look at Blood Vessels
Amazing Heart Facts
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Your heart is about the same size as your fist.
An average adult body contains about 5 quarts of
blood.
All the blood vessels in the body joined end to end
would stretch 62,000 miles or two and a half times
around the earth.
The heart circulates the body’s supply
about 1,000 times each day.
The heart pumps the equivalent of 5,000
to 6,000 quarts of blood each day.
“Flow chart” of Blood Flow
• From Body
• Right Atrium
• Right Ventricle
• To Lungs
• From Lungs
• Left Atrium
• Left Ventricle
• To Body
http://www.smm.org/heart/heart/pumping-f.htm
Circulation - Blood
Circulation - Blood