Made up of….
• The circulatory system
• Heart, blood and vessels
Functions of the heart,
blood and vessels
• Circulate blood to all
parts of the body
• Transport water,
oxygen and nutrients
• Remove wastes,
dioxide, from cells
• Maintain body
• Composed of four chambers
• Two Atria (upper chambers) & two Ventricles (lower
• The Atria receive blood from the body (and lungs),
the ventricles pump blood back out into the body.
• Label the various structures of the heart
• Color in the heart as to where there would be oxygen rich
blood (red) and oxygen poor (blue) blood
• Think about
• How does the blood become ‘oxygen rich?’
• Where does it go after it becomes oxygen rich?
• Where does it go after it ‘drops off’ its oxygen?
• Arteries – Carry oxygen rich blood to the working
• Veins – Carry oxygen poor blood back to the heart
• Capillaries – site of gas exchange
• Contains blood cells, fluid, minerals and gases
• Each persons has approximately 4-5 L of blood
• Blood is made up of
• Red Blood Cells (O2 Carrying)
• White Blood Cells (immune system)
• Platelets (clotting cells)
• Plasma (90% water, nutrient carrying)
• Blood Cells (45%)
• Blood Plasma (55%)
• Arteries – Arterioles –
Capillaries – Venules –
• The aorta is the largest
artery in the body. The
left ventricle pushes the
blood into the aorta and
onto the rest of the body.
• The artery walls are
elastic so they are able
to expand with each
• When you take your
heart rate, you are
feeling the pressure of
the blood being pushed
into the arterial system.
• Arteries further reduce in size to become arterioles as the
network of blood vessels work their way into the depths
of the body.
• Bleeding from an artery can be recognised by the blood
spurting out with each heart beat and by its bright red
(oxygen rich) colour.
• Coronary Artery – supplies the hearts chambers with
oxygen and nutrients.
• Heart attacks are often caused by a blockage of the
• Smoking, drinking, eating fatty foods and lack of exercise
contribute to coronary artery blockages.
• The exchange of
nutrients and waste
between the body and
blood cells occurs in the
• Heat from cells is also
absorbed into blood
through the capillaries
• Exchange of materials is
easy as capillaries are only
one cell thick.
• When you begin to exercise
capillaries dilate to allow
increased blood flow.
• Other capillaries come into
use through the opening of
• A long term exercise program may increase the number
of capillaries supplying blood to muscles, allowing an
increased oxygen supply to muscle and removal of
• Veins carry blood back to the heart.
• Veins have no pulse, blood flow is steady and constant.
• The walls of veins are thin and not as elastic as artery
• The return of blood to
the heart depends on
contraction of skeletal
• Veins are squeezed by
muscle as they contract.
• One way valves working
against gravity and
prevent backflow of
blood to organs and