The Cardiovascular System
• The cardiovascular
system transports
materials to and
from your cells.
• The cardiovascular
system is made up
of three parts:
blood, the heart,
and blood vessels.
• Blood is a connective
tissue made up of red
blood cells, white blood
cells, platelets and
plasma
• Plasma is the fluid part
of blood.
• Red blood cells, white
blood cells, and platelets
float in the plasma
• Red blood cells supply
your cells with oxygen
• Each RBC contains a
protein called
hemoglobin
• Hemoglobin gives
blood its red color
• White blood cells destroy
pathogens
• Some WBC’s squeeze out of
vessels and move around in
tissues, searching for
pathogens. When they find a
pathogen, they engulf it
• Other WBC’s release
chemicals called antibodies,
which help destroy
pathogens.
Platelets
• Platelets are pieces of
larger cells which
release chemicals in
damaged vessels and
cause fibers to form
• The fibers make a
“net” that traps
blood cells and stops
bleeding.
3- red blood cell
5- platelet
Red & White Cells in a blood
vessel
Blood Cells in a
small blood
vessel
Red Blood Cell
White Blood Cell
• Your heart is
about the size of
your fist.
• The heart pumps
oxygen-poor
blood to the
lungs and
oxygen-rich
blood to the body
• Your heart has a
left side and a
right side that are
separated by a
thick wall
• Each side has an
upper chamber
and a lower
chamber
• Upper chamber is
called an atrium
• Lower chamber is
called a ventricle
• Valves are
located between
the atria and
ventricles
• As blood moves
through the
heart, the valves
close and prevent
blood from
going backward.
• The right heart
receives poorly
oxygenated blood
from the body
(blue in color),
while the left heart
receives highly
oxygenated blood
from the lungs (red
in color).
Blood Vessels
• Blood flows throughout your body in blood vessels
• A blood vessel is a hollow tube that transports blood
• There are three types of blood vessels—arteries,
capillaries, and veins
• Arteries carry blood away
from the heart.
• Arteries have thick walls
that contain a layer of
smooth muscle
• When blood is pumped
out of the heart at high
pressure, these thick walls
have the strength to
withstand it.
• Capillaries are the smallest blood
vessels in your body.
• Capillary walls are only one cell
thick
• No cell in the body is more
than three or four cells away
from a capillary
• Veins carry blood
back to the heart.
• When skeletal
muscles contract,
they squeeze nearby
veins and help push
blood toward the
heart
• If all the blood
vessels in your
body were
strung together,
the total length
would be more
than twice the
circumference of
the Earth.
•
• Where does blood
get its oxygen?
• It gets it from your
lungs during
pulmonary
circulation
• Pulmonary
circulation is
between your heart
and lungs.
• When oxygen-rich blood returns to
the heart from the lungs, it must be
pumped to the rest of the body.
• The circulation of blood between
the heart and the rest of the body is
called systemic circulation
Exercise and blood flow
• Physical activity causes as
much as 10 times more
blood to be sent to the
muscles than when your
body is at rest.
• Less blood is sent to the
kidneys and the digestive
system so that more blood
can go to the skeletal
muscles, brain, heart, and
lungs